•GEOLOGY   OF 

PETROLEUM 


ST'} 


BY 
WILLIAM  HARVEY  EMMONS,  PH.D. 

PROFESSOR  AND  HEAD  OF  DEPARTMENT  OF  GEOLOGY  AND  MINERALOGY,  UNIVERSITY 
OF  MINNESOTA;  DIRECTOR,  MINNESOTA  GEOLOGICAL  SURVEY;   FORMERLY 

.       •  GEOLOGIST,    SECTION   OF  METALLIFEROUS  DEPOSITS,   UNITED 

STATES   GEOLOGICAL  SURVEY. 


FIRST  EDITION 


McGRAW-HILL  BOOK  COMPANY,  INC. 

NEW  YORK:  370  SEVENTH  AVENUE 

LONDON:     6  &  8  BOUVERIE  ST.,  E.  C.  4 

1921 


'Y 


COPYRIGHT,  1921,  BY  THE 
McGRAW-HiLL  BOOK  COMPANY,  INC. 


MAPI,*:     PHKSS     Y  O  K  K    PA 


PREFACE 

I  have  attempted  in  this  volume  to  present  as  briefly  as  is 
practicable  a  perspective  of  the  data  of  the  geology  of  petroleum. 
The  work  is  based  on  a  series  of  lectures  which  for  several  years 
past  I  have  offered  in  courses  on  economic  geology  at  the  Uni- 
versity of  Minnesota.  These  lectures  have  been  rewritten  and 
expanded.  The  material  was  first  prepared  some  years  ago  to 
be  included  as  a  chapter  in  "The  Principles  of  Economic  Geol- 
ogy," recently  issued.  The  chapter  was  so  large,  however,  that 
to  have  included  it  would  have  defeated  some  of  the  purposes 
of  that  volume.  It  was  withdrawn  and  rewritten  and  is  offered 
here. 

This  book  was  prepared  to  be  used  as  a  text  for  students  who 
wish  to  acquire  some  knowledge  of  the  geology  of  petroleum,  espe- 
cially for  those  who  have  already  studied  the  operation  of  geologic 
processes  and  the  principles  of  stratigraphy.  I  have  introduced 
sections  showing  the  strata  of  many  oil  fields  and  many  details 
of  stratigraphy  which  it  will  be  desirable  to  omit  in  classroom 
work.  The  best  results  will  probably  be  obtained  by  omitting 
much  of  the  material  presented  for  certain  fields  and  empha- 
sizing that  relating  to  other  fields,  especially  those  of  which  the 
students  already  have  some  general  knowledge. 

Within  the  last  few  years  I  have  had  many  opportunities  to 
visit  the  geologic  departments  of  petroleum  engineers  and  cor- 
porations and  have  been  impressed  with  the  large  amount  of 
carefully  prepared  data  which  they  possess.  I  can  not  hope  to 
add  much,  if  anything,  to  these  data.  Nevertheless,  by  offering 
a  little  about  many  fields  I  trust  I  have  rendered  a  service  to  the 
profession.  This  volume  is  not  intended  to  serve  as  a  handbook 
of  petroleum  geology.  I  have  included  in  it,  however,  brief 
sketches  of  the  geology  of  many  oil  fields  and  numerous  refer- 
ences to  the  literature  treating  them,  and  I  hope  it  will  serve 
some  of  the  needs  of  a  geologist  who  is  undertaking  the  study  of  a 
field  new  to  him. 

I  realize  that  there  may  be  serious  omissions  and  possibly  errors 
in  the  presentation  and  discussion  of  so  much  material  gathered 

v 


430015 


vi  PREFACE 

from  so  many  sources.  I  shall  esteem  it  a  favor  if  anyone  whose 
statements  I  may  have  misquoted  or  misinterpreted  will  set  me 
right,  and  if  those  who  have  had  .superior  opportunities  for  study 
of  certain  districts  will  correct  any  wrong  impressions  I  may  have 
given. 

In  general  I  have  followed  the  standard  uses  of  terms.  With 
respect  to  the  use  of  the  term  monocline,  however,  I  have  de- 
parted from  the  once  standard  usage  and  have  classed  as  mono- 
clinal  structural  features  those  strata  on  the  flanks  of  other 
folds  that  outcrop  and  are  sealed  above  the  reservoirs.  In  this 
usage  I  have  followed  many  of  the  highest  authorities  in  the 
field  of  petroleum  geology.  Such  a  use,  I  believe,  is  justified.  It 
is  convenient  and  in  many  cases  it  greatly  simplifies  expression 
and  it  is  understood  by  all  geologists  working  in  the  field  of  petro- 
leum geology. 

I  acknowledge  my  indebtedness  to  Professors  C.  R.  Stauffer 
and  F.  F.  Grout  and  to  Messrs.  G.  M.  Schwartz  and  John  Gruner, 
of  the  Department  of  Geology  and  Mineralogy  of  the  University 
of  Minnesota,  and  to  Mr.  Julius  Segall  and  Mr.  Frank  Notestein, 
who  have  read  critically  sections  of  the  volume;  to  Prof.  J.  A. 
Bownocker  who  has  read  the  sections  on  Ohio  fields  and  to  Mr. 
N.  0.  Barrett  who  has  read  the  section  on  Illinois  fields;  and  to 
Messrs.  O.  F.  Ernster  and  Karl  A.  Berg  for  many  services, 
especially  in  connection  with  the  preparation  of  drawings.  I 
have  endeavored  suitably  to  acknowledge  sources  of  information 
by  footnote  references. 

W.  H.  EMMONS. 

UNIVERSITY  OF  MINNESOTA,  MINNEAPOLIS, 
December,  1920. 


/ 


CONTENTS 

CHAPTER  I 

PAGE 

PREFACE    v 

INTRODUCTION- 1 

General  Occurrence  of  Petroleum 1 

Uses 3 

Historical  Notes 3 

Geographic  Distribution  of  Petroleum 6 

Geologic  Distribution  of  Petroleum 10 

Kinds  of  Strata  Containing  Petroleum  and  Gas 10 

Geologic  Ages  of  Strata  Producing  Petroleum  and  Gas    ....  11 

CHAPTER  II 

SURFACE   INDICATIONS   OF   PETROLEUM  AND   MATERIALS  ASSOCIATED 

WITH  IT 16 

Distribution 16 

Classification  of  Hydrocarbons  and  Allied  Substances 17 

Oil  Seeps 23 

Oil  Ponds 25 

Solid  Bitumens 25 

Bone  Deposits  in  Asphalt 27 

Bituminous  Rocks 27 

Test  for  Oil  in  Rocks 28 

Bituminous  Dikes 29 

Gas  Seeps 33 

"Paraffin  Dirt" 36 

Mud  Volcanoes 36 

Mud  Dikes 38 

Oil  Shales 38 

.    Burnt  Shales 39 

Salt  Water  Seeps 39 

Sulphur  and  Sulphur  Compounds •.    .    .    .  40 

CHAPTER  III 

OPENINGS  IN  ROCKS 41 

Sizes  of  Openings 41 

Origin  of  Openings 42 

Primary  Openings 42 

Intergranular  Spaces  in  Sedimentary  Rocks 42 

Bedding  Planes 44 

Vesicular  Spaces 44 

vii 


Vlil  CONTENTS 

PAGE 

Openings  in  Pumice 44 

Miarolitic  Cavities 45 

Submicroscopic  Spaces 45 

Secondary  Openings 45 

Openings  Formed  by  Solutions 45 

Openings  Due  to  Shrinkage 45 

Openings  Due  to  the  Force  of  Crystallization 46 

Openings  Due  to  Greater  Stresses 47 

CHAPTER  IV 

ASSOCIATION  OF  PETROLEUM  AND  SALT  WATER 48 

CHAPTER  V 

RESERVOIR  ROCKS  AND  COVERING  STRATA 53 

Reservoir  Rocks 53 

General  Character 53 

Mineral  Composition  of  Reservoir  Rocks 53 

Capacities  of  Reservoir  Rocks 59 

Coverings  of  Reservoirs  .   . 65 

Kinds  of  Covering  Strata 65 

Thickness  of  Covering  Strata 66 

CHAPTER  VI 

SOME  PROPERTIES  OF  PETROLEUM  AND  GAS 68 

Color .  68 

Odor 68 

Density 69 

Viscosity 71 

Composition  of  Petroleum 71 

Composition  of  Natural  Gases 74 

CHAPTER  VII 

ORIGIN  OF  PETROLEUM  AND  NATURAL  GAS 80 

Inorganic  Theories v    .    .    .    .  80 

Organic  Theories 83 

Association  of  Petroliferous  Strata  and  Coal 88 

Accumulation  of  Petroleum  in  Beds  Formed  Under  Arid  Condi- 
tions    90 

Temperatures  of  Oil  Fields 92 

CHAPTER  VIII 

MAPS  AND  LOGS 96 

Structural  Contour  Maps 96 

Well  Logs 101 


CONTENTS  ix 
CHAPTER^? 

PA^GE 

ACCUMULATION  OF  PETROLEUM 1*05 

The  Anticlinal  Theory 105 

Segregation  Due  to  Differences  in  Surface  Tension 112 

Fractionation  of  Petroleum  in  Clay 117 

CHAPTEJ 

STRUCTURAL  FEATURES  OF  OIL  AND  GAS  RESERVOIRS 120 

Reservoirs  in  Anticlines  and  Domes 120 

Amplitudes  of  Anticlinal  Folds  that  Form  Reservoirs 131 

Shapes  of  Anticlines  that  Form  Reservoirs 133 

Origin  of  Anticlines  that  Form  Reservoirs 134 

Arrangement  of  Anticlines  that  Form  Reservoirs 137 

Segregation  of  Oil  on  Basin  ward  Sides  of  Folds 138 

Reservoirs  in  Monoclines 139 

Monoclines  Sealed  by  Overlying  and  Underlying  Clays  or  Shales 

Joining  Above  Reservoirs 142 

Monoclines  Sealed  by  Faults 144 

Monoclines  Sealed  by  Local  Cementation  of  the  Reservoir  Rock  146 

Monoclines  Sealed  by  Asphalt 146 

Monoclines  Sealed  by  Unconformities 149 

Monoclines  Sealed  by  Igneous  Intrusions 152 

Reservoirs  in  Flat-lying  Beds 153 

Aclines 153 

Terraces 153 

Reservoirs  iji  -Synclines 154 

Reservoirs  Formed  by  Fissures • 156 

Accumulation  in  Sands  of  Irregular  Pore  Space 159 

Accumulation  at  Unconformities 160 

Successions  of  Petroliferous  Strata 161 

Distances  Covered  in  the  Migration  of  Petroleum 162 

Minimum  Inclination  Necessary  for  Migration 163 

Behavior  of  Folds  in  Depth .164 

CHAPTER  (xu 

DEFORMATION  OF  PETROLIFEROUS  STRATA •.  170 

Deformation  in  Unconsolidated  Materials 170 

Influence  of  Faulting  on  Reservoirs 170 

CHAPTER  XII 

METAMORPHISM  OF  PETROLEUM  BY  DYNAMIC  AGENCIES 173 

CHAPTER  XIII 

GAS  PRESSURE  AND  OIL  RECOVERY 180 

Gas  Pressure 180 

Behavior  of  Certain  Wells  That  Yield  Oil  and  Gas  .                     .  183 


X  CONTENTS 

CHAPTER  XIV 

PETROLIFEROUS  PROVINCES  AND  PETROLEOGENIC  EPOCHS 

CHAPTER  XV 

APPALACHIAN,  LIMA-INDIANA  AND  MICHIGAN   FIELDS 195 

Introduction 195 

Appalachian  Oil  Fields • 206 

General  Features 206 

New  York,  Pennsylvania,  and  West  Virginia 210 

Eastern  Ohio 225 

References  for  New  York,  Pennsylvania,  Ohio  and  West  Virginia  231 

Kentucky 233 

Tennessee 244 

Alabama      247 

Lima-Indiana  Field 248 

Michigan  Field 254 

CHAPTER  XVI 

ILLINOIS 256 

Introduction 256 

Crawford,  Lawrence  and  Adjoining  Counties 261 

Central  and  Western  Illinois 264 

References  for  Illinois  Fields 269 

CHAPTER  XVII 

MlD-CoNTINENT  FlELDS 271 

General  Features 271 

Northeastern    Oklahoma,    Southeastern    Kansas,    Arkansas,    and 

Missouri • 279 

General  Statement 279 

Oklahoma 281 

Salient  Features 281 

Gushing  Pool    .    . 287 

Glenn  Pool 292 

Bristow  Quadrangle "...  295 

Nowata  County  Pools 295 

Washington  County  Pools 296 

Osage  County  Pools 297 

Kay  County  Pools 298 

Billings,  Noble  County 298 

Garber,  Garfield  County 299 

Muskogee  County  Pools 300 

Okmulgee  County  Pools 304 

References  for  Oklahoma   .    .    .    .  • 304 

Arkansas ; 306 

Kansas 307 

Missouri  .314 


CONTENTS  xi 

PAGE 

Red  River  Region,  Oklahoma  and  Texas 316 

General  Features 316 

Healdton,  Oklahoma '.    ...   320 

Loco,  Oklahoma 321 

Duncan,  Oklahoma 322 

Lawton,  Oklahoma  . 322 

Cement,  Oklahoma 323 

Madill,  Oklahoma 324 

Wichita  and  Clay  Counties,  Texas 324 

North-central  Texas  Fields 328 

Fields  East  of  Balcones  Fault,. Texas 337 

General  Features 337 

Corsicana  Field 339 

Mexia-Groesbeck  Field 342 

Thrall  Field 343 

Northwestern  Louisiana  and  Northeastern  Texas 346 

General  Features 346 

Caddo  Field 351 

De  Soto-Red  River  Field 355 

Pelican  Field 355 

References  for  Texas  Fields 356 

References  for  Louisiana  Fields 356 

CHAPTER  XVIII 

PROSPECTS  IN  MISSISSIPPI,  ALABAMA  AND  GEORGIA 358 

Mississippi 358 

Alabama 360 

Georgia 362 

CHAPTER  XIX 
GULF  COAST  FIELDS  OF  TEXAS  AND  LOUISIANA 36# 

CHAPTER  XX 

ROCKY  MOUNTAIN  FIELDS 375 

Wyoming 375 

General  Features 375 

Salt  Creek 382 

Powder  River 385 

Big  Muddy  Dome 386 

Douglas 386 

Lander 389 

Maverick  Springs 389 

Pilot  Butte 390 

Central  Wyoming 390 

Rock  River 392 

Lost  Soldier  .  .  392 


xii  CONTENTS 

PAGE 

Moorcroft 392 

Newcastle 393 

Upton-Thornton 394 

Buck  Creek 394 

Mule  Creek 394 

Spring  Valley 396 

Labarge .    , 396 

Big  Horn  Basin 397 

References  for  Wyoming 408 

Montana 409 

General  Features 409 

Stillwater  Basin 411 

Lake  Basin 413 

Porcupine  Dome 415 

Musselshell  Valley 418 

North-central  Montana 420 

Birch  Creek-Sun  River  Area 421 

Blackfeet  Reservation 421 

Bowdoin  Dome 426 

Eastern  Montana 426 

North  Dakota 428 

Colorado 429 

General  Features 429 

Florence 429 

Boulder 431 

DeBeque 432 

Rangely 433 

White  River 434 

Urado 434 

Utah .    . 435 

Green  River  District 435 

Hanksville 435 

Salt  Lake  Basin 435 

San  Juan  Field •  .    . 438 

Virgin  City 439 

New  Mexico 439 

Idaho  and  Oregon 441 

CHAPTER  XXI 

PACIFIC  COAST  FIELDS 442 

California 442 

General  Features 442 

Coalinga 444 

Lost  Hills 449 

McKittrick,  Sunset,  and  Midway 450 

Kern  River 457 

Santa  Clara.                                                                                   .  458 


CONTENTS  xin 

PAGE 

Summerland 460 

Santa  Maria 462 

Los  Angeles 463 

Puente  Hills .466 

References  for  California 469 

Alaska  Fields 470 

CHAPTER  XXII 

CANADA  AND  NEWFOUNDLAND 475 

Ontario 476 

Nova  Scotia 483 

New  Brunswick 483 

Quebec 484 

Western  Canada 485 

References  for  Canada 494 

Newfoundland 495 

CHAPTER  XXIII 

MEXICO 497 

CHAPTER  XXIV 

EUROPE  EXCEPT  RUSSIA 507 

Great  Britain 507 

France 509 

Germany 513 

Italy 514 

Sicily 517 

Galicia 517 

General  Features 517 

Boryslaw 520 

Opaka-Schodnica-Uryoz 523 

Western  Galicia 524 

Rumania 525 

CHAPTER  XXV 

RUSSIA,  MESOPOTAMIA,  PERSIA,  AND  EGYPT 533 

Russia ' 533 

General  Features 533 

Baku 535 

Grozny 541 

Maikop .    .  542 

Taman  and  Kertch 543 

Sviatoi 543 

Cheleken  Island 544 

Transcaspian  Province 545 

.  545 


XIV 


CONTENTS 


PAGE 

Ferghana 546 

Northern  Russia 546 

Mesopotamia 546 

Persia 547 

Egypt 549 

CHAPTER  XXVI 

BURMA  AND  OCEANICA 553 

Burma • 553 

Yenangyaung 554 

Yenangyat-Singu 555 

Sumatra 557 

Java 559 

Borneo 560 

Philippine  Islands 561 

Japan  and  Formosa 566 

New  Zealand 568 

Australia 569 

CHAPTER  XXVII 

CARIBBEAN  ISLANDS •/....  571 

Cuba * 571 

Haiti  and  Santo  Domingo 573 

Barbados 574 

Trinidad 574 

CHAPTER  XXVIII 

SOUTH  AMERICA 580 

Venezuela 580 

Colombia 581 

Peru 584 

Ecuador 590 

Argentina  and  Bolivia 591 

INDEX.                                                                                        595 


GEOLOGY 

OF 

PETROLEUM 

CHAPTER  I 

INTRODUCTION 
GENERAL  OCCURRENCE  OF  PETROLEUM 

Petroleum,  or  rock  oil,  is  an  inflammable  mixture  of  oily  hydro- 
carbons that  exudes  from  the  earth  or  is  pumped  up  and  is  used 
extensively  for  generating  heat,  light,  and  power  and  for  lubricat- 
ing machinery. 

Asphaltum  is  a  solid  bitumen,  and  maltha  a  semifluid  bitumen; 
both  are  residues  formed  by  the  partial  evaporation  or  inspissation 
of  petroleum. 

Natural  gas,  or  rock  gas,  is  an  aeriform  mixture  that  is  found  at 
or  beneath  the  surface  of  the  earth  and  is  used  as  an  illuminant,  for 
fuel,  and  for  generating  power.  Natural  gas  is  commonly  asso- 
ciated with  petroleum. 

Petroleum  and  natural  gas  are  formed  by  the  decomposition  of 
plant  and  animal  remains  that  have  been  buried  with  sediments  in 
the  sea.  They  are  almost  never  found  in  commercial  quantities  in 
igneous  rocks,  in  metamorphosed  rocks,  or  in  fresh-water  sedi- 
ments not  associated  with  marine  strata.  They  generally  originate 
in  muds,  clays,  or  shales,  or  much  less  commonly  in  marls  or  lime- 
stones. Petroleum  and  natural  gas  can  not  ordinarily  accumulate 
in  shales  in  large  amounts,  because  in  such  rocks  adequate  open- 
ings are  generally  not  available.  As  a  rule  they  accumulate  in 
sands  or  sandstones  associated  with  clays  or  shales,  or  in  porous 
limestones.  In  age  the  petroleum-bearing  strata  range  from  Ordo- 
vician  to  Recent. 

Salt  water  is  generally  associated  with  petroleum  and  is  believed 
to  be  sea  water  that  filled  the  pores  of  the  sands  when  they  were 
laid  down  in  the  sea.  Waters  from  oil-bearing  strata  differ  from 
sea  water  in  concentration  and  in  composition,  but  there  are 

1 


OF  PETROLEUM 

\reasons  I'Q-  si? pposing  tfaah  changes  have  taken  place  since  the 
original  sea  water  was  stored  in  the  rocks.  Not  all  oil-bearing 
strata  are  saturated  with  salt  water;  some  contain  very  little  water, 
and  in  at  least  two  fields  the  oil  is  floated  on  water  that  is  practi- 
cally free  from  salt. 

Where  rocks  are  saturated  with  petroleum,  natural  gas,  and  salt 
water,  the  oil  is  generally  found  above  the  water,  and  as  a  rule  the 
gas  is  found  above  the  oil.  This  rearrangement  is  due  chiefly  to 
gravity. 

As  a  rule  the  strata  that  contain  petroleum  are  folded.  In  some 
places  they  are  only  gently  folded;  in  others  they  are  thrown  into 
sharp  folds,  the  beds  dipping  20  to  30  degrees  or  more.  In  consoli- 
dated rocks,  such  as  shales,  sandstones,  and  limestones,  which  have 
been  intensely  deformed  by  faulting  and  close  folding,  oil  is  gener- 
ally not  found  in  large  amounts.  In  unconsolidated  series  of  rocks, 
such  as  clays,  marls,  and  sands,  large  accumulations  are  known  in 
areas  of  highly  complicated  structures.  In  some  regions  uncon- 
solidated oil-bearing  rocks  have  been  intensely  faulted  by  thrust 
faults  and  overturned,  yet  they  still  retain  large  accumulations  of 
petroleum. 

Many  of  the  oil  fields  are  on  monoclines,  on  which  are  developed 
secondary  folds,  such  as  anticlines,  synclines,  domes,  and  struc- 
tural terraces.  In  rocks  that  are  highly  saturated  with  oil  and  in 
beds  that  dip  very  gently  the  oil  gathers  in  domes,  if  any  are  avail- 
able, but  accumulation  takes  place  also  in  very  gentle  folds  and  in 
structural  features  that  are  not  "closed"  (see  p.  96),  such  as  plung- 
ing anticlines  and  terraces.  In  rocks  that  are  less  highly  saturated 
with  oil  in  a  country  containing  sharp  folds,  the  accumulation  is 
generally  in  areas  of  closed  structures,  such  as  domes,  or  in  traps 
such  as  are  formed  where  an  open  fold  is  crossed  by  a  fault. 

Not  all  reservoirs  are  porous  beds  on  anticlines.  Any  body  of 
porous  rock  seate^-above  in.any  manner  may  under  certain  condi- 
tions supply  a  reservoir  for  the  accumulation  of  either  petroleum 
or  natural  gas. 

If  the  porous  strata  in  areas  of  folded  structure  are  not  saturated 
with  water,  oil  will  descend  on  the  folds  until  it  occupies  the 
flanks  of  synclines,  and  if  no  water  is  present  it  tends  to  move  down 
to  the  bottoms  of  the  folds.  In  strata  containing  openings  of 
unequal  size,  oil  and  gas  accumulate  in  the  larger  openings,  the 
water  being  drawn  by  capillary  attraction  into  the  smaller  ones. 


INTRODUCTION  3 

USES 

In  its  crude  state  petroleum  is  used  extensively  for  fuel.  It  has 
a  high  evaporating  power  per  unit  of  weight  and  is  in  demand  for 
use  under  locomotive  and  marine  boilers.  The  heavy  oils  are  used 
for  fuel  more  generally  than  the  lighter  oils,  because  as  a  rule  the 
heavy  oil  will  not  yield  such  valuable  products.  Heavy  oils  are 
used  also  in  the  crude  state  for  road  dressing,  and  for  making 
roofing. 

In  refining  petroleum,  it  is  broken  up  by  a  process  of  distillation 
into  many  products,  including  petroleum  ether,  gasoline,  naphtha, 
kerosene,  lubricating  oils,  vaseline,  paraffin  wax,  and  petroleum 
coke.  Each  of  these  materials  has  a  variety  of  uses.  Ether  is 
used  in  medicine  as  a  cooling  agent  and  for  priming  internal-com- 
bustion engines  in  cold  weather.  Gasoline  is  used  as  fuel  in  inter- 
nal-combustion engines,  for  cleaning  cloth  and  other  substances, 
and  as  a  solvent  of  oil  and  grease.  Naphtha  is  used  for  approx- 
imately the  same  purposes  and  much  commercial  gasoline  is  a  mix- 
ture of  gasoline  and  naphtha.  Kerosene  is  used  principally  for 
illumination  and  as  a  fuel  for  tractors.  Lubricating  oils  are  the 
heavy  viscous  products  obtained  by  refining  petroleum.  They 
are  used  for  lubricating  machinery  and  when  highly  refined  for 
medicinal  purposes,  especially  as  laxatives.  Paraffin  wax  is  used 
for  making  candles,  for  sealing  preserved  fruits  and  vegetables,  and 
as  a  preservative.  It  is  used  also  for  medicinal  purposes,  especially 
in  the  treatment  of  burns.  Petroleum  coke  is  used  in  metallurgic 
processes,  as  a  fuel,  and  for  making  carbons  for  batteries  and  arc 
lights. 

Many  petroleum  refineries  do  not  produce  all  the  products  men- 
tioned. Some  "topping  plants"  distill  off  the  lighter  products, 
such  as  may  be  used  as  fuel  for  internal-combustion  engines,  and 
sell  the  heavier  residues  for  fuel  oil  or  for  road  dressing. 

Asphalt  is  formed  in  nature  by  the  drying  up  of  petroleum, 
chiefly  where  it  exudes  at  the  surface.  It  is  used  for  making  pave- 
ments, roofings,  and  other  building  materials.  Some  oils  on  refin- 
ing yield  an  artificial  asphalt  that  is  much  like  the  natural  product 
and  is  used  for  similar  purposes. 

HISTORICAL  NOTES 

The  bitumens  were  known  to  the  ancients  in  the  earliest  historic 
era.  The  Bible  refers  to  oil  obtained  from  a  rock  and  to  pitch 


GEOLOGY  OF  PETROLEUM 


WORLD'S  PRODUCTION  OF  CRUDE  PETROLEUM  SINCE  18 

(After  J.  D.  Northr 


Year 

Rumania 

United 
Statesa 

Italy 

Canada 

Russia 

Galicia 

Japan  and 

Formosa 

German 

1857..  . 

1,977 

1858.  . 

3,560 

1859... 

4,349 

2  666 

1860.  . 

8,542 

500,000 

36 

1861..  . 

17,279 

2  113,609 

29 

1862. 

23,198 

3,056,690 

29 

11,775 

1863.  .  . 

27,943 

2,611,309 

58 

82,814 

40,816 

1864. 

33,013 

2,116,109 

72 

90,000 

64,686 

1865.  .  . 

39,017 

2,497,700 

2,265 

110,000 

66,542 

1866  .  . 

42,534 

3,597,700 

992 

175,000 

83,052 

1867 

50  838 

3,347,300 

791 

190,000 

119,917 

1868.  .  . 

55,369 

3,646,117 

367 

200,000 

88,327 

1869. 

58  533 

4,215,000 

144 

220,000 

202,308 

1870.  .  . 

83,765 

5,260,745 

86 

250,000 

204,618 

1871 

90  030 

5,205,234 

273 

269,397 

165,129 

1872.  .  . 

91,251 

6,293,194 

331 

308,  100 

184,391 

1873. 

104,036 

9,893,786 

467 

365,052 

474,379 

1874.  .  . 

103,177 

10,926,945 

604 

168,807 

583,751 

149,837 

1875.  .  . 

108,569 

8,787,514 

.  813 

220,000 

697,364 

158,522 

"4,'566 

1876.  .  . 

111,314 

9,132,669 

2,891 

312,000 

1,320,528 

164,157 

7,708 

1877.  .  . 

108,569 

13,350,363 

2,934 

312,000 

1,800,720 

169,792 

9,560 

1878.  .  . 

109,300 

15,396,868 

4,329 

312,000 

2,400,960 

175,420 

17,884 

1879.  .  . 

110,007 

19,914,146 

2,891 

575,000 

2,761,104 

214,800 

23,457 

1880.  .  . 

114,321 

26,286,123 

2,035 

350,000 

3,001,200 

229,120 

25,497 

"9,'3 

1881... 

121,511 

27,661,238 

1,237 

275,000 

3,601,441 

286,400 

16,751 

29,2 

1882.  .  . 

136,610 

30,349,897 

1,316 

275,000 

4,537,815 

330,076 

15,549 

58,0 

1883.  .  . 

139,486 

23,449,633 

1,618 

250,000 

6,002,401 

365,160 

20,473 

26,7 

1884.  .  . 

210,667 

24,218,438 

2,855 

250,000 

10,804,577 

408,120 

27,923 

46,1 

1885.  .  . 

193,411 

21,858,785 

1,941 

250,000 

13,924,596 

456,400 

29,237 

41,3 

1886.  .  . 

158,606 

28,064,841 

1,575 

584,061 

18,006,407 

305,884 

37,916 

73,8 

1887.  .  . 

181,907 

28,283,483 

1,496 

525,655 

18,367,781 

343,832 

28,645 

74,2 

1888.  .  . 

218,576 

27,612,025 

1,251 

695,203 

23,048,787 

466,537 

37,436 

84,7 

1889.  .  . 

297,666 

35,163,513 

1,273 

704,690 

24,609,407 

515,268 

52,811 

68,2 

1890.  .  . 

383,227 

45,823,572 

2,998 

795,030 

28,691,218 

659,012 

51,420 

108, 

1891... 

488,201 

54,292,655 

8,305 

755,298 

34,573,181 

630,730 

52,917 

108,  : 

1892... 

593,175 

50,514,657 

18,321 

779,753 

35,774,504 

646,220 

68,901 

101,  i 

1893.  .  . 

535,655 

48,341,066 

19,069 

798,406 

40,456,519 

692,669 

106,384 

99,  ! 

1894.  .  . 

507,255 

49,344,516 

20,552 

829,104 

36,375,428 

949,146 

171,744 

122,  i 

1895.  .  . 

575,200 

52,892,276 

25,843 

726,138 

46,140,174 

1,452,999 

141,310 

121,  ' 

1896.  .  . 

543,348 

60,960,361 

18,149 

726,822 

47,220,633 

2,443,080 

197,082 

145,  I 

1897.  .  . 

570,886 

60,475,516 

13,892 

709,857 

54,399,568 

2,226,368 

218,559 

165,  '. 

1898.  .  . 

776,238 

55,364,233 

14,489 

758,391 

61,609,357 

2,376,108 

265,389 

183,  < 

1899.  .  . 

1,425,777 

57,070,850 

16,121 

808,570 

65,954,968 

2,313,047 

536,079 

192,  I 

1900.  .  . 

1,628,535 

63,620,529 

12,102 

913,498 

75,779,417 

2,346,505 

866,814 

358,25 

1901... 

1,678,320 

69,389,194 

16,150 

756,679 

85,168,556 

3,251,544 

1,110,790 

313,6: 

1902.  .  . 

2,059,935 

88,766,916 

18,933 

530,624 

80,540,044 

4,142,159 

1,193,038 

353,6^ 

1903.  .  . 

2,763,117 

100,461,337 

17,876 

486,637 

75,591,256 

5,234,475 

1,209,371 

445,81 

1904.  .  . 

3,599,026 

117,080,960 

25,476 

552,575 

78,536,655 

5,947,383 

1,419,473 

637,45 

1905.  .  . 

4,420,987 

134,717,580 

44,027 

634,095 

54,960,270 

5,765,317 

1,472,804 

560,  9£ 

1906.  .  . 

6,378,184 

126,493,936 

53,577 

569,753 

58,897,311 

5,467,967 

1,710,768 

578,61 

1907.  .  . 

8,118,207 

166,095,335 

59,875 

788,872 

61,850,734 

8,455,841 

2,001,838 

756,6 

1908.  .  . 

8,252,157 

178,527,355 

50,966 

527,987 

62,186,447 

12,612,295 

2,070,145 

1,009,2 

1909.  .  . 

9,327,278 

183,170,874 

42,388 

420,755 

65,970,350 

14,932,799 

1,889,563 

1,018,8 

1910... 

9,723,806 

209,557,248 

50,830 

315,895 

70,336,574 

12,673,688 

1,930,661 

1,032,52 

1911... 

11,107,450 

220,449,391 

74,709 

291,096 

66,183,691 

10,519,270 

1,658,903 

1,017,04 

1912... 

12,976,232 

222,935,044 

53,778 

243,336 

68,019,208 

8,535,174 

1,671,405 

1.031,05 

1913... 

13,554,768 

248,446,230 

47,198 

228,080 

62,834,356 

7,818,130 

1,942,009 

6995,76 

1914.  .  . 

12,826,579 

265,762,535 

39,849 

214,805 

67,020,522 

65,033,350 

2,738,378 

&995.  76 

1915... 

12,029,913 

281,104,104 

43,898 

215,464 

68,548,062 

4,158,899 

3,118,464 

&99S.76 

1916... 

^10,  298,  208 

300,767,158 

50,585 

198,123 

^72,801,110 

6,461,706 

2,997,178 

&995,76 

1917.  .  . 

&2,  681,  870 

335,315,601 

&50.334 

205,332 

^69,000,000 

*5,  965,  447 

2,898,654 

6995,76 

Total.. 

142,992,465 

4,252,644,003 

947,289 

24,112,529 

1,832,583,017 

148,459,653 

36,065,454 

15,952,86 

or 

2.04 

60.78 

0.02 

0.35 

26.19 

2.12 

0.52 

0.2 

"Quantity  marketed.        ^Estimated.        'Includes  British  Borneo. 


INTRODUCTION 


YEARS  AND  COUNTRIES,  IN  BARRELS  OF  42  GALLONS 
S.  Geological  Survey) 


India 

Dutch  East 
Indies 

Peru 

Mexico 

Argen- 
tina 

Trini- 
dad 

Egypt 

Other 
Countries 

Total 

Year 



1,977 

..1857 

3,560 

.  .  1858 



6,349 

.  .  1859 

508,578 

..I860 

2,130,917 

..1861 

3,091,692 

.  .  1862 

2,762,940 

.  .  1863 

2,303,780 

.  .  1864 

2,715,524 

.  .  1865 

3,899,278 

.  .  1866 

3,708,846 

.  .  1867 

3,990,180 

.  .  1868 

4,695,985 

.  .  1869 

5,799,214 

1870 

5,730,063 

"1871 

6,877,267 

1872 

10,837,720 

.  '.  1873 

11  933  121 

1874 

9,  977',  348 

'.  '.  1875 

11,051,267 

..1876 

15,753,938 

.  .  1877 

18,416,761 

.  .  1878 

23,601,405 

.  .  1879 

30,017,606 

1880 

31  !  992!  797 

'.  '.  1881 

35  704  288 

1882 

30,255,479 

..1883 

35,968,741 

.  .  1884 

36,764,730 

..1885 

47,243,154 

.1886 

47,807  083 

1887 



52,164,597 

.1888 

94  ,'250 

61,507,095 

.1889 

18,065 

76,632,838 

.1890 

90,131 

91,100,347 

.1891 

!42,284 

88,739,219 

.1892 

198,969 

"600,  'OOO 

92,038,127 

.1893 

27,218 

688,170 

89,335,697 

.1894 

71,536 

1,215,757 



103,662,510 

.1895 

29,979 

1,427,132 

47,536 

114,159,183 

.1896 

45,704 

2,551,649 

70,831 

121,948,575 

.1897 

42,110 

2,964,035 

70,905 

124,924,682 

.1898 

40,971 

1,795,961 

89,166 

131,143,742 

.1899 

78,264 

2,253,355 

274,800 

149,132,116 

.1900 

30,716 

4,013,710 

274,800 

:"i6,345 

»20,'000 

167,434,434 

.1901 

I/,  363 

2,430,465 

286,725 

40,200 

626,000 

182,006,076 

.1902 

10,259 

5,770,056 

278,092 

75,375 

&36.000 

194,879,669 

.1903 

85,468 

6,508,485 

345,834 

125,625 

640,000 

218,204,391 

.1904 

37,098 

7,849,896 

447,880 

251,250 

630,000 

215,292,167 

.1905 

15,803 

8,810,657 

536,294 

502,500 

630,000 

213,415,360 

.1906 

44,162 

9,982,597 

756,226 

1,005,000 

'"ioi 

630,000 

264,245,419 

.1907 

47,038 

10,283,357 

1,011,180 

3,932,900 

11,472 

'"i69 

630,000 

285,552,746 

.1908 

76,517 

11,041,852 

1,316,118 

2,713,500 

18,431 

57,143 

620.000 

298,616,405 

.1909 

37,990 

11,030,620 

1,330,105 

3,634,080 

20,753 

142,857 

620,000 

327,937,629 

.1910 

51,203 

12,172,949 

1,368,274 

12,552,798 

13,119 

285,307 

"9,'iso 

620,000 

344,174,355 

.1911 

16,672 

10,845,624 

1,751,143 

16,558,215 

47,007 

436,805 

205,905 

620,000 

352,446,598 

.1912 

30,149 

11,172,294 

2,133,261 

25,696,291 

130,618 

503,616 

94,635 

620,000 

383,547,399 

.1913 

09,792 

••11,834,802 

1,917,802 

26,235.403 

275,500 

643,533 

777,038 

620,000 

403,745,342 

.1914 

02,674 

'12,  386,  800 

2,487,251 

32,910,508 

516,120 

6750,000 

262,208 

610,000 

427,740,129 

.1915 

91,137 

"13,  174,  399 

2,550,645 

40,545,712 

793,920 

928,581 

411,000 

625,000 

461,493,226 

.1916 

78,843 

'12,928,955 

2,533,417 

55,292,770 

1,144,737 

1,599,455 

,008,750 

"7,004,973 

506,702,902 

.1917 

52,365 

175,103,267 

21,878,285 

22,082,472 

2,974,778 

5,347,466 

2,768,686 

14,599,973 

5,996,674,563 

.Total 

1  40 

2.50 

0.31 

3.18 

0.04 

0  08 

0  04 

0  20 

...% 

Istimated  in  part. 

icludea  19,167  barrels  produced  in  Cuba,  127,743  barrels  in  Venezuela,  and  6,856,063  barrels  in  Persia. 


6  GEOLOGY  OF  PETROLEUM 

used  for  making  tight  the  seams  of  boats.  The  Persian  fire  wor- 
shipers had  shrines  at  gas  seepages  in  the  Apsheron  Peninsula, 
Russia,  and  until  recent  years  the  followers  of  Zoroaster  made 
pilgrimages  to  that  region  and  to  Holy  Island,  nearby,  in  the 
Caspian  Sea.1  There  are  numerous  references  to  the  bitumens  in 
Greek  and  Latin  literature.  The  Romans  used  petroleum  in  lamps. 
The  bitumens  were  obtained  at  oil  seeps  or  springs  or  in  shallow 
pits,  dug  at  the  surface,  into  which  the  oil  would  flow. 

Many  place  names  refer  to  pitch  or  oil — for  example,  Pechel- 
bronn  (pitch  spring),  near  Hagenau,  Alsace;  La  Brea  (pitch  or 
asphalt),  a  name  used  for  many  places  in  Spanish  countries;  the 
Persian  Kir,  the  Russian  Neft,  and  the  Burmese  Yenang. 

In  modern  times  petroleum  has  been  exploited  for  more  than  a 
century  in  Alsace,2  where  deep  shafts  were  sunk  into  the  oil-bear- 
ing formations.  In  Burma  deep  wells  were  put  down  by  hand, 
and  oil  was  bailed  out  of  them  with  buckets.  These  methods  are 
slow  and  laborious  and  because  of  the  gas  associated  with  petro- 
leum are  dangerous  and  frequently  result  in  loss  of  life.  The 
exploitation  of  petroleum  on  a  considerable  scale  began  about  1860, 
when  modern  drilling  practice  was  introduced.  The  machinery 
and  technology  of  drilling  were  developed  largely  in  the  Appalach- 
ian region,  in  the  United  States,  and  in  the  Petrolia  region,  Lamb- 
ton  County,  Ontario,  which  were  among  the  first  regions  to  be 
exploited  on  the  modern  scale.  The  "Canadian  rig"  and  "Ameri- 
can rig"  are  widely  used  throughout  the  world. 

GEOGRAPHIC  DISTRIBUTION  OF  PETROLEUM 

On  pages  4  and  5  is  a  table  showing  the  production  of  petro- 
leum to  1917,  inclusive,  with  the  percentage  of  the  whole  that  each 
country  produced.  In  order  of  output  the  countries  rank  as  fol- 
lows: United  States,  Russia,  Mexico,  Dutch  East  Indies,  Galicia, 
Rumania,  India,  Japan,  Canada,  Peru,  Germany,  Trinidad, 
Argentina,  Egypt,  Italy.  Since  1917  no  large  fields  have  been  dis- 
covered or  opened  except  in  Persia  and  Colombia,  of  which  the 
statistics  are  not  available.  Figs.  1  and  2  show  the  distribution 
of  the  oil  fields.  The  United  States  and  Russia  together  have  pro- 
duced about  87  per  cent  of  the  world's  petroleum  output  to  1917. 

THOMPSON,  A.  B. :  The  Oil  Fields  of  Russia,  p.  96,  London,  1904. 
REDWOOD,  BOVERTON:  A  Treatise  on  Petroleum.    Vol.  1,  p.  48,  London, 
1913. 


INTRODUCTION  7 

North  America  has  produced  64.31  per  cent;  Europe,  including 
Russia1,  Rumania,  Galicia,  Germany,  and  Italy,  has  produced  30.60 
perc  ent;  Asia  and  Oceanica,  including  the  Dutch  East  Indies,India, 
and  Japan,  4.42  per  cent;  South  America,  including  Peru,  Trinidad, 
and  Argentina,  0.43  per  cent;  and  Africa,  0.04  per  cent.  The 
Western  Hemisphere  has  produced  64.74  per  cent,  and  the  Eastern 
Hemisphere  has  produced  35.06  per  cent  of  the  total.  Australia 
and  Africa,  except  northern  Egypt*,  are  essentially  unproductive. 
The  Northern  Hemisphere  has  produced  96.95  per  cent,  and  the 
Southern  Hemisphere,  including  all  of  the  Dutch  East  Indies 
(where  some  of  the  oil  is  found  north  of  the  Equator),  Peru,  and 
Argentina,  has  produced  2.85  per  cent.  It  is  noteworthy  also  that 
92.29  per  cent  of  the  world's  production  has  come  from  the  north 
temperate  zone,  and  the  remaining  7.51  per  cent  has  come  from 
fields  south  of  the  Tropic  of  Cancer.  The  continents  rank  in  order 
of  output:  North  America,  Europe,  Asia,  South  America,  and 
Africa.  The  most  thoroughly  explored  countries  have  been  the 
most  productive. 

Clapp,  who  has  devoted  considerable  study  to  both  Asia  and 
South  America,  states  that  the  South  American  output  will  prob- 
ably rise  in  the  course  of  a  few  years  to  second  place;  although  in 
his  opinion2  the  final  rank  of  the  continents  by  total  production, 
when  fully  developed,  is  likely  to  be  as  follows:  North  America, 
Asia,  South  America,  Europe,  Africa.  This  is  a  decidedly  opti- 
mistic view  of  the  future  supply  of  Asia  and  South  America,  con- 
sidering the  great  production  of  European  Russia  and  the  unde- 
veloped territory  on  both  sides  of  the  Caucasus  Mountains  and  in 
other  parts  of  Russia  in  Europe. 

In  the  immediate  future  Persia  and  Colombia  are  likely  to  be- 
come increasingly  important  as  producers  of  oil,  and  an  increased 
production  is  expected  from  Mexico  and  Oceanica.  Except  in  the 
United  States  there  has  been  very  little  development  of  territory 
far  away  from  areas  exhibiting  surface  indications  of  oil.  Large 
production  may  be  expected  when  the  same  methods  of  prospecting 
areas  of  favorable  structure  in  consolidated  rocks  that  are  applied 
in  North  America  shall  be  extensively  applied  in  other  fields. 

'Production  of  the  Emba  field,  north  of  Caspian  Sea  is  included  with  that  of 
European  Russia. 

2CLAPP,  F.  G. :  Petroleum  Resources  of  South  America.  Am.  Inst.  Min. 
Eng.  Bull.  130,  p.  1744. 


GEOLOGY  OF  PETROLEUM 


FIG.  1. — Map  showing  producing  oil  fields  of  Western  Hemisphere.     (A  few 
prospective  fields  are  shown.) 


INTRODUCTION 


FIG.  2. — Map  showing  producing  oil  fields  of  Eastern  Hemisphere.     (A  few 
prospective  fields  are  shown.) 


10  GEOLOGY  OF  PETROLEUM 

The  United  States,  by  bringing  in  new  fields,  has  steadily 
advanced  production.  It  is  not  expected  that  as  many  new  fields 
will  be  discovered  in  the  future.  Probably  some  will  be  brought 
in,  new  pools  on  extensions  of  oil  fields  will  be  discovered,  and 
deeper  reservoirs  will  be  developed  in  the  producing  fields.  Never- 
theless many  investigators  who  have  given  most  thought  to  the 
matter  are  of  the  opinion  that  the  United  States  is  not  very  far 
from  the  zenith  of  its  production.  As  the  world's  greatest  con- 
sumer of  petroleum  and  its  products  the  United  States  must  look 
to  foreign  fields  in  the  near  future,  or  we  must  learn  to  do  without 
some  of  the  things  which  we  have  come  to  regard  as  necessary. 

The  world's  oil  supply  has  been  discussed  by  Smith,1  and  by 
White.2 

White  gives  an  estimate,  prepared  by  geologists  of  the  United 
States  Geological  Survey,  of  the  oil  remaining  in  the  strata  in  the 
United  States,  January  1,  1919.  He  states  that  the  quantity  avail- 
able is  6,740,000,000  barrels.  At  the  present  rate  of  consumption 
this  would  last  the  United  States  about  17  years.  White  published 
an  estimate  of  the  supplies  of  the  principal  countries4  of  the  world 
that  are  known  to  contain  oil.  This  estimate,  which  was  prepared 
by  Eugene  Stebinger,  is  stated  on  page  11.  The  unused  resources 
of  the  United  States  and  Alaska  are  taken  as  the  unit,  1.00,  esti- 
mated to  be  7,000,000,000  barrels. 

GEOLOGIC  DISTRIBUTION  OF  PETROLEUM 

**f  Kinds  of  Strata  Containing  Oil  and  Gas. — The  world's  petroleum 

\l  comes  from  sedimentary  beds,  practically  all  of  it  from  sands,  sand- 

/    stones,  conglomerates,  and  porous  limestones  and  dolomites.     The 

/      deposits  the  world  over  are  held  in  by  coverings  of  shale,  clay,  or 

\    marl.3    The  producing  beds  almost  without  exception  are  marine 

\  strata  or  strata  of  fresh-water  origin  that  are  closely  associated 

i  with  marine  strata.     The  organic  material  from  which  the  oil  is 

I  derived  finds  lodgment  in  clays  and  marls  when  they  are  deposited, 

/  and  the  oil  accumulates  in  sands  and  other  porous  rocks  that  are 

/   associated  with  the  clays  and  marls.  ^The  bodies  of  strata  most 

^N     ^MITH,  G.  O.:  A  Foreign  Oil  Supply  for  the  United  States.      Advance 
Publication  No.  157,  Trans.,  Amer.  Inst.  Min.  Eng.,  February,  1920. 

2WniTE,  DAVID:   Petroleum  Resources  of  the  World.      Oil  and  Gas  Jour., 
vol.  19,  No.  2,  pp.  76-82,  and  vol.  19,  No.  3,  pp.  54-62,  1920. 
3Reservoir  rocks  are  discussed  on  p.  53 ;  cover  caps  on  p.  65. 


INTRODUCTION 


11 


OIL  RESOURCES  OF  PRINCIPAL  OIL  CONTAINING  REGIONS  OF  THE  WORLD. 
(Estimate  of  Eugene  Stebinger0) 


COUNTY  OR  REGION 

Relative 
Value 

Millions  of 
Barrels 

TTnifpH  Stntp^  and  Alaska 

1.00 

7,000 

0.14 

995 

0.65 

4,525 

Northern  South  America,  including  Peru  
Southern  South  America  including  Bolivia           .    ... 

0.82 
0.51 

5,730 
3,550 

Altrpria  and  Ecrvot 

0.13 

925 

Ppr^ifl  and  IVlesoDotamia 

0.83 

5,820 

Southeastern   Russia,   southwestern  Siberia,   and   the 
region  of  the  Caucasus                      

0.83 

5,830 

Rumania  Galicia  and  western  Europe              

0.16 

1,135 

Northern  Russia  and  Saghalien    

0.13 

925 

Japan  and  Formosa    

0.18 

1,235 

China                                           

0.20 

1,375 

0.14 

995 

East  Indies  

0.43 

3,015 

Total  eastern  hemisphere                  

6.15 
3.03 

43,055 
21,255 

Total  western  hemisphere                                         '   .... 

3.12 

21,800 

Total  north  of  eouator 

5  20 

36,400 

Total  south  of  eouator                              

0.95 

6,655 

aOil  and  Gas  Journal,  vol.  19,  No.  3,  p.  54,  1920.  _jJ 

common  in  oil  fields  are  those  in  which  thick  shales,  clays,  or  marls        ) 
alternate  with  relatively  thin  sands.  ^ 

Geologic  Age  of  Strata  Producing  Petroleum  and  Gas. — Oil  or 
gas,  or  both,  are  found  in  strata  ranging  from  the  Cambrian  to  the 
Recent.  Large  amounts  are  found  in  the  rocks  formed  during  the 
Paleozoic,  Mesozoic,  and  Cenozoic  eras.  All  the  oil  produced  in 
Europe  and  in  Asia  is  derived  from  the  Cenozoic  formations,  except 
a  small  production  in  Derbyshire,  England,  which  comes  from 
Paleozoic  beds,  and  a  small  production  in  Galicia,  Alsace  and  Han- 
nover where  oil  is  derived  from  the  Mesozoic.  In  the  Eurasian 
fields  the  Miocene  and  Oligocene  are  the  most  productive  strata, 
although  the  Eocene  yields  considerable  oil  in  Galicia. 

In  Mexico,  Venezuela,  and  Argentina  the  principal  producing 
strata  are  Cretaceous.  In  Colombia  oil  is  derived  from  the  Creta- 
ceous and  the  Tertiary.  The  production  of  Barbados  and  most  of 
that  of  Trinidad  are  derived  from  Miocene  strata. 


12  GEOLOGY  OF  PETROLEUM 

In  North  America  large  amounts  of  petroleum  are  found  in 
strata  of  Paleozoic,  Mesozoic,  and  Cenozoic  age.  The  Paleozoic 
strata  produce  the  oils  of  the  Appalachian  region,  the  Illinois  field, 
and  the  Oklahoma,  Kansas,  and  northern  Texas  fields.  They 
yield  also  the  oil  produced  in  Canada. 

The  Cambrian  has  produced  a  little  gas  in  New  York. 

Oil  and  gas  are  found  in  the  Trenton  limestone  (Ordovician)  in 
the  Lima-Indiana  field  of  Ohio  and  Indiana.  The  Trenton  pro- 
duces some  oil  also  in  southeast  Illinois  and  in  the  Dover  West 
field,  just  east  of  Lake  St.  Clair  in  Kent  County,  Ontario.  In  New 
York  gas  is  derived  from  the  Trenton. 

The  Silurian  produces  a  little  oil  in  the  Appalachian  field.  It  is 
the  chief  source  of  gas  in  the  Clinton  gas  field  of  eastern  Ohio,  and 
it  yields  some  gas  also  in  Ontario,  west  and  south  of  Niagara  Falls, 

The  Devonian  yields  oil  and  gas  in  New  York,  Pennsylvania. 
West  Virginia,  Ohio,  Kentucky,  Tennessee,  Indiana,  and  Ontario. 
In  Pennsylvania  both  lower  and  upper  Devonian  are  productive; 
in  West  Virginia  the  Chemung  is  barren  but  the  Catskill  is  pro- 
ductive. In  Canada  limestone  of  the  Devonian  is  the  chief  produc- 
ing formation.  The  Devonian  limestone  has  produced  oil  and  gas 
also  in  eastern  Kentucky. 

The  Mississippian  produces  oil  in  Pennsylvania,  West  Virginia, 
Ohio,  Kentucky,  Illinois,  western  Indiana,  and  Texas.  In  Penn- 
sylvania, West  Virginia,  Illinois,  and  northern  Texas  it  is  highly 
productive. 

The  Pennsylvanian  strata  produce  oil  in  the  Appalachian  region 
and  in  Illinois.  Oil  and  asphalt  are  found  in  Pennsylvanian  beds 
also  near  Princeton,  Indiana.  The  Pennsylvanian  Cherokee  shale 
is  the  chief  oil  and  gas  bearing  formation  in  Kansas  and  Oklahoma. 
The  Pennsylvanian  is  productive  also  in  northern  Texas.  Penn- 
sylvanian rocks  carry  oil  in  the  San  Juan  field,  Utah.  Some  oil  is 
found  in  the  Embar  (Pennsylvanian  and  Permian),  near  Lander, 
Wyoming. 

A  little  oil  is  found  in  the  Permian  (Red  Beds)  in  Oklahoma,  at 
Virgin  City,  Utah,  and  in  Pecos  Valley,  New  Mexico. 

The  Trinity  sand  (Cretaceous,  Comanche)  carries  oil  in  the 
Medill  field,  Oklahoma,  and  asphalt  in  Pike  County,  Arkansas. 
At  both  places  it  is  unconformable  above  the  flexed  and  eroded 
Carboniferous  beds  that  are  believed  to  have  supplied  the  oil. 

The  Upper  Cretaceous  carries  the  oil  in  eastern  Texas  and 


INTRODUCTION  13 

northern  Louisiana  and  in  the  Big  Horn  Basin,  Salt  Creek,  Big 
Muddy,  and  many  other  fields  in  Wyoming.  A  little  oil  is  found 
in  the  Graneros  (Benton)  at  Moorcroft,  Wyoming,  and  in  the 
Benton  in  the  Labarge  and  Spring  Valley  fields,  Wyoming.  Oil  is 
found  in  the  Pierre  (Upper  Cretaceous)  in  the  Shannon  field, 
Wyoming;  in  fractured  Pierre  shales  at  Florence,  Colorado;  and  in 
a  sandstone  included  in  the  Pierre  in  the  Boulder  field,  Colorado. 
Oil  is  found  in  the  Mancos  (Upper  Cretaceous)  in  the  Rangely 
field,  Colorado,  and  possibly  in  the  Mesaverde  (Upper  Cretaceous) 
in  the  DeBeque  field,  Colorado.  In  the  McKittrick-Sunset  region, 
California,  a  little  oil  appears  in  the  Chico  (Cretaceous)  shales. 

The  Tertiary  formations  are  important  oil  carriers  in  the  Gulf 
coast  fields — for  example,  Spindletop,  Sour  Lake,  Saratoga,  Bat- 
son,  Dayton,  and  Humble,  all  in  Texas,  and  Jennings  and  Anse  La 
Butte,  in  Louisiana.  In  the  Wasatch  (continental  Eocene)  asphalt 
is  found  in  the  Uinta  Basin  of  Utah  and  Colorado,  and  some  oil 
is  found  also  at  Vernal,  Utah.  In  the  California  fields  the  prin- 
cipal oil-bearing  formations  are  Eocene  (Tejon,  Sespe,  and  Topa- 
topa)  and  Miocene  (Vaqueros,  Monterey,  Modelo,  Puente,  Santa 
Margarita,  Fernando,  and  Jacalitos). 

Oil  is  found  also  in  Pleistocene  beds  in  the  Summerland  and 
Puente  Hills  regions,  California.  Gas  is  found  in  Pleistocene  beds 
of  Lake  Bonneville,  Utah,  and  asphalt  in  Salt  Lake. 

Gum  beds  and  a  lubricating  oil  are  found  near  the  base  of  the 
glacial  drift  in  Lambton  County,  Ontario.  This  oil  obviously  has 
escaped  from  lower  beds. 

The  subjoined  tables  summarize  the  data  as  to  the  age  of  the 
principal  reservoirs  of  oil  and  gas, 


14 


GEOLOGY  OF  PETROLEUM 


AGE  OF  PRINCIPAL  PETROLEUM  RESERVOIRS  IN  THE  UNITED  STATES 


1 
\ 

Pennsylvania 

West  Virginia 

i 

Kentucky 

I 

Indiana 

'o 

a 

HH 

Missouri 

M 

Oklahoma 

Arkansas 

s 

0) 

Louisiana 

Wyoming 

California  | 

Pleistocene.  .  . 

4- 

Pliocene  

4- 

Miocene  

4- 

Oligocene.  .  . 

4- 

4- 

a-4- 

.1 

Eocene  

4- 

Upper 
Cretaceous  . 
Lower 
Cretaceous  . 
Jurassic     .... 

+ 

+ 

+ 

+ 

4- 

Triassic  .... 

Permian  

4- 

4- 

b  + 

Pennsylvanian 

4- 

_j_ 

_|_ 

_|_ 

V 

_|_ 

4- 

_j_ 

4- 

gas 

Mississippian  . 
Devonian.  .  .  . 

•' 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

•• 

Silurian  
Ordovician.  .  . 
Cambrian  .... 

gas 
gas 
gas 

J 

i 

t 

i 

I 

°A  little  oil  is  found  in  the  White  River  formation  (Oligocene)  in  the  Douglas  field. 
&Embar  formation,  partly  Pennsylvanian 

AGE  OF  PRINCIPAL  PETROLEUM  RESERVOIRS  IN  THE  CARIBBEAN  REGION  AND 

SOUTH  AMERICA 


i 

T3 

05 

2  «» 

*%$ 

§ 

8 

•^ 

8 

a 

-1 

0) 

5 

g3 
•°  a 

«•%'£ 
§  a  Q 

S  0 

03  -a 

gj 

<o 

6 

3 

a 

I 

c 

'H 

h 

i 

V 

> 

*i 

3-3 

T3  C  'o 

US 

3  3 

.13 

11 

ii 

< 

Pleistocene  

Pliocene.  . 

°  + 

Miocene  

•f 

+ 

i* 

Oligocene 

+ 

+? 

Eocene  

+ 

+? 

& 

.. 

Cretaceous.  .  . 

4r 

4-? 

-j- 

+ 

+ 

4- 

Jurassic  

•H 

«In  Trinidad  oil  exudes  from  Pliocene  strata. 
Miocene  strata. 


It  is  probably  derived  in  the  main  from 


INTRODUCTION 


15 


AGE  OF  PRINCIPAL  PETROLEUM  RESERVOIRS  IN  THE  EASTERN  HEMISPHERE 


feg 

ff  03 

-S3 

Boryslaw, 
Galicia 

Schodnica, 
Galicia 

Rumania 

11 

>>« 

S'3 

O  3 

<5« 

Maikop, 
Russia  | 

a 
1 

Burma 

Sumatra 

1 

| 
•-» 

England 

Pleistocene 

Pliocene 

0_j_ 

+ 

Miocene  
Oligocene      

*+ 

+ 
'  + 

"+ 

-j- 

+ 
+ 

+ 

'+ 

+ 

C  + 

+ 

+ 

+ 

Eocene  
Cretaceous 

°  + 
+ 

-f 

•• 

Jurassic.        

Triassic 

Permian  

Upper  Carbonifer- 
ous   

Lower  Carbonifer- 
ous   

-(- 

• 

aSubordinate. 

^Miocene  subdivided  into  Maeotic,  Sarmatian.  Tortonian,  Helvetian,  and  Burdigalian; 
each  carries  petroleum  in  places. 

clrrawady  River  fields,  include  Yenangyaung  and  Yenangyat-Singu. 

dln  Alsace  the  principal  petroliferous  series  is  lower  OHgocene  and  includes  marine  and  non- 
marine  sediments.  A  little  oil  is  found  in  Mesozoic  rocks. 

cThe  upper  Oligocene  is  the  richest  petroliferous  formation. 

/Probably  upper  Oligocene. 

^Eocene  is  the  most  important  series. 


CHAPTER  II 

SURFACE  INDICATIONS  OF  PETROLEUM  AND  MATERIALS 
ASSOCIATED  WITH  IT 

Indications  of  oil  deposits  include  oil  and  the  materials  that  have 
been  formed  by  the  drying  of  oil — asphaltum,  gilsonite,  paraffins, 
maltha,  etc. — as  well  as  the  common  associates  of  oil,  such  as 
bituminous  rock,  oil  shale,  burned  shale,  gas,  salt  water,  and  in 
some  regions  sulphur  and  its  compounds  and  acid  waters.  Mud 
volcanoes  and  in  some  regions  mud  dikes,  indicating  the  existence 
of  mud  volcanoes  that  have  been  eroded,  are  evidence  of  gas.  In 
places  "paraffin  dirt"  (see  page  36)  has  been  found  above  deposits 
of  oil  or  gas. 

Any  indication  of  oil  or  gas  is  to  be  interpreted  in  connection 
with  its  geologic  setting,  namely,  the  rock  column,  the  structure, 


FIG.  3. — Sketch  showing  oil  seeps  at  outcrop  of  petroliferous  stratum  and 
an  accumulation  of  oil  and  gas  (black)  many  miles  away  down  the  dip  from 
the  outcrop. 

and  the  degree  of  metamorphism  shown  in  associated  beds  that 
may  be  present.  The  geologic  conditions  at  the  surface — the  rocks 
present  and  their  attitude — are  indications  of  what  may  be  ex- 
pected at  depths.  These  are  treated  in  other  chapters. 

Distribution. — Oil  springs  or  asphaltites  are  found  in  many  oil 
fields  and  are  generally  regarded  as  favorable  indications.  The 
springs  may  exude  at  outcrops  of  the  oil  sands  or  limestones  in 
which  the  oil  is  stored  (Fig.  3),  or  they  may  exude  from  fault  fis- 
sures, joints,  or  other  conduits  in  beds  that  cover  the  oil-bearing 
stratum.  Where  oil  exudes  from  the  oil-bearing  stratum  the 
springs  merely  indicate  that  the  stratum  is  petroliferous  and  that 
the  deposits  are  being  scattered.  Petroleum  deposits  commonly 
are  not  situated  below  the  points  of  issue,  but  in  some  regions  they 

16 


SURFACE  INDICATIONS  OF  PETROLEUM 


17 


CLASSIFICATION  OF  HYDROCARBONS  AND  ALLIED  SUBSTANCES 

(After  Blake,  Eldridge,  and  Others) 
CLASSIFICATION  OF  NATURAL  HYDROCARBONS 


Gaseous  .  . 


Marsh  gas. 
"Natural  gas." 


Fluid (Naphtha. 

Petroleum. 


Viscous  (malthite) 


Bituminous .  .  .  \  Elastic , 


Asphaltite  . . 


Solid. . 


Coal. 


{Maltha. 
Mineral  tar 
Brea. 
Chapapote. 

.  (Elaterite  (mineral  caoutchouc). 
\Wurtzilite.a 

Albertite 

Impsonite. 

Grahamite. 

Nigrite. 

Uintaite  (gilsonite). 

[Lignite. 

j  Bituminous  coal. 
.  I  Semibituminous  coal. 
[Anthracite  coal. 

[Succinite  (amber). 
.<Copalite. 
[Ambrite,  etc. 

.J  Ozokerite. 
\Hatchettite,  etc. 


fFichtelite. 

Crystalline \Hartite,  etc. 

oWurtzilite  might  perhaps  better  be  classed  with  the  asphaltites. 

are  down  the  dip  many  miles  away,  at  places  where  the  structure  is 
favorable  for  retaining  oil.  In  southeastern  Kansas,  southwestern 
Missouri,  and  northeastern  Oklahoma  the  Pennsylvanian  oil  sands 
that  yield  prolific  supplies  farther  west  in  Oklahoma  and  Kansas 
are  exposed  at  the  surface.  Here  and  there  along  their  outcrops1 
1  ADAMS,  G.  I.,  HA  WORTH,  ERASMUS,  and  CRANE,  W.  R.:  Economic  Geology 
of  the  lola  Quadrangle,  Kansas.  U.  S.  Geol.  Survey  Bull  238,  p.  16, 1904. 


Resinous. 


Cereous . 


18 


GEOLOGY  OF  PETROLEUM 


CLASSIFICATION  OF  NATURAL  AND  ARTIFICIAL  BITUMINOUS  COMPOUNDS 
(After  Eldridge) 

Mixed    with   limestone     fSeyssel,  Val  de  Travers,  Lobsan,  Utah, 
("asphal tic  limestone")  \     and  other  localities 

Mixed  with  silica  and  sand]  California,  Kentucky,  Utah,  and  other 
("asphaltic  sand").          \     localities.     "Bituminous  silica." 


iMixed  with  earthy  matter  fTrmidad   Cub     Californi     Utah. 
("asphaltic  earth").        \ 


Bituminous  schists. 


Fluid. 


Viscous. 


Solid, 


Canada,  California,  Kentucky,  Virginia, 
and  other  localities. 

Thick  oils  from  the  evaporation  of  petro- 
leum. 

(Gas  tar. 
'\Pitch. 

Refined  Trinidad  asphaltic  earth. 
Mastic  of  asphaltite. 
Gritted  asphaltic  mastic. 
Paving  compounds. 

and  also  in  the  zinc  mines  of  the  Joplin  region, 1  deposits  of  bitumen 
and  of  partly  dried  out  oil  are  found  in  considerable  quantities  at 
the  base  of  the  Pennsylvanian  strata.  At  Tar  Spring,  six  miles 
north  of  Miami,  Oklahoma,  a  heavy  bitumen  oozes  in  considerable 
quantities  at  the  base  of  the  Pennsylvanian.  At  that  horizon  the 
bitumen  is  so  abundant  as  to  interfere  with  prospecting  for  metals 
with  the  churn  drill.  These  deposits  are  surface  suggestions  of  the 
Oklahoma-Kansas  oil  fields,  which  lie  many  miles  to  the  west. 
Above  the  oil  pools  themselves,  oil  seeps  are  generally  lacking  in 
this  region. 

Not  all  petroleum  springs,  asphaltite  deposits,  and  gas  seeps 
occur  at  the  outcrops  of  the  oil  sands  or  other  oil-bearing  forma- 
tions. In  some  regions  these  evidences  of  oil  are  found  at  the 
crests  or  on  the  flanks  of  anticlines,  where  the  oil  has  seeped  through 
the  cover  of  the  reservoir.  (See  Fig.  4.)  Where  the  hydrocarbons 
escape  through  fissures  or  joint  planes,  valuable  deposits  may  occur 
not  far  away,  or  even  directly  below  their  places  of  issue.  In  many 

^IEBENTHAL,  C.  E. :  Origin  of  the  Zinc  and  Lead  Deposits  of  the  Joplin 
Region,  Missouri,  Kansas,  and  Oklahoma.  U.  S  Geol.  Survey  Bull.  606,  p.  205, 
1915 


SURFACE  INDICATIONS  OF  PETROLEUM          19 

fields  surface  evidences  of  oil  are  very  clearly  exposed  at  or  near  the 
tops  of  structural  features  that  have  yielded  oil.  This  is  very 
common  where  rocks  are  unconsolidated  and  is  a  noteworthy 
feature  of  many  fields  where  Tertiary  beds  are  petroliferous.  In 
California,  on  the  Gulf  coast,  in  Alsace,  Galicia,  Rumania,  Baku, 
Russia,  Burma  (Yenangyaung  and  Yenangyat),  Java,  Sumatra, 
and  elsewhere  in  Oceanica  either  asphalt,  oil  seeps,  gas  seeps,  mud 
volcanoes,  mud  dikes,  or  salt  springs  appear  near  or  directly  above 
deposits  of  petroleum.  In  some  of  these  districts  it  is  clear  that 
oil  or  gas  has  issued  through  fissures  at  or  near  the  tops  of  the 
petroliferous  folds. 

In  North  America  superficial  indications  of  oil  are  found  in  many 
oil-bearing  regions.  Oil  Spring,  in  Allegany  County,  New  York, 
and  Oil  Creek,  in  western  Pennsylvania,  were  known  before  the 
Appalachian  oil  field  was  exploited.  At  Smith's  Ferry,1  in  the 


10  Miles, 


FIG.  4. — Sketch  showing  oil  seeps  at  crest  of  fold  above  oil  accumulation 

(black). 

Beaver  quadrangle,  Pennsylvania,  the  oil  floating  on  the  Ohio 
River  was  gathered  and  sold  as  "Seneca  oil"  for  medicinal  pur- 
poses. In  West  Virginia  a  grahamite  dike  was  worked  before  the 
Appalachian  field  was  developed.  Burning  Springs,  West  Vir- 
ginia, is  at  a  gas  seep  on  the  Burning  Springs- Volcano-Eureka 
anticline,  which  has  yielded  much  petroleum.  At  Oil  Springs, 
Lambton  County,2  Ontario,  a  liquid  extracted  from  the  "gum 
beds"  yielded  "gum  oil,"  before  the  Oil  Springs  dome  was  exploited 
for  petroleum.  Oil  seeps  were  found  upon  the  Salt  Creek  dome, 
and  on  many  other  uplifts  in  Wyoming.  An  oil  spring  exists  in  the 
Boulder  field,  Colorado,  although  it  was  not  this  spring  that  led  to 
drilling.  An  oil  seep  issues  not  far  from  the  productive  part  of  the 
Florence  field,  Colorado.  Oil  seeps  or  asphalt  deposits  are  present 

1WooLSEY,  L.  H. :  Economic  Geology  of  the  Beaver  Quadrangle,  Pennsyl- 
vania. U.  S.  Geol.  Survey  Bull.  286,  p.  76,  1906. 

2WiLLiAMS,  M.  Y.:  Oil  Fields  of  Southwestern  Ontario.  Canada  Dept. 
Mines  Summary  Rept.,  1918,  part  E,  p.  30,  1919. 


20  GEOLOGY  OF  PETROLEUM 

in  the  San  Juan  field,  Utah.  In  the  California  oil  fields  asphalt  is 
almost  invariably  present  in  large  amounts,  and  oil  seeps  and  tar 
springs  abound.  Such  evidences  are  present  in  the  Coalinga, 
McKittrick,  Sunset,  Santa  Clara,  Santa  Maria,  Summerland, 
Puente  Hills,  Los  Angeles,  and  some  other  fields. 

In  some  fields  where  oil  seeps  are  lacking  gas  seeps  have  led  to 
drilling. 

At  Findlay,  Ohio,  gas  issuing  into  cisterns  led  to  the  discovery 
of  the  field.  The  Caddo  field,  Louisiana,  was  drilled  because  of 
the  gas  bubbling  up  in  Caddo  Lake. 

In  the  "salt  dome"  fields  of  the  Gulf  coast,  surface  indications  of 
oil  and  gas  abound.  Because  much  salt  and  sulphur  are  associated 
with  the  oil  these  substances  also,  when  appearing  at  the  surface, 
are  regarded  as  indications  of  petroleum.  Small  mounds  rising 
above  the  general  level  of  the  flat  country  mark  some  of  the  oil 
districts  and  have  led  to  drilling.  Not  all  the  mounds  have  proved 
productive,  and  not  all  the  districts  are  on  mounds,  but  practically 
all  the  producing  pools  are  marked  by  the  escape  of  gas.  Gas 
bubbles  in  water  or  gas  seeps  were  noted  at  Spindletop,  Sour  Lake, 
Saratoga,  Batson,  Dayton,  and  Humble,  Texas,  and  in  the  Jen- 
nings field  and  at  Anse  La  Butte  and  Welsh,  Louisiana.  Sulphur 
was  noted  in  the  soil  at  Spindletop,  and  "sour"  water  at  Sour  Lake 
and  Saratoga,  Texas.  At  Sour  Lake  oil  and  asphalt  appeared 
also,  and  at  Saratoga,  oil. 

In  the  Tuxpam-Tampico  field,  Vera  Cruz,  Mexico,  the  rocks  dip 
eastward  from  the  mountains  to  the  coast  at  low  angles.  At  many, 
places  dikes,  sills,  and  stocks  of  basaltic  rocks  intrude  the  sedi- 
mentary beds.  Most  of  the  surface  indications  of  oil  are  closely 
associated  with  the  basalts,  and  hundreds  of  them  occur  through- 
out the  plain.  Among  the  localities  where  oil  seeps  are  abundant 
are  Panuco,  Dos  Bocas,  Casiano,  Tres  Hermanos,  Ojo  de  Brea, 
Chapapotillo,  and  Monte  Grande.1 

Manjak,  a  tar  formed  by  the  drying  of  oil,  is  exploited  in  Bar- 
bados, where  it  is  found  at  the  outcrops  of  Miocene  sandstones 
and  shales.  Earth  saturated  with  tar  is  found  at  Tarry  Gully, 
near  St.  Andrew.  At  the  "boiling  spring"  near  St.  Andrew  inflam- 
mable gas  issues  from  a  pool  of  water.  Wells  sunk  in  the  Miocene 
of  Barbados  yielded  a  little  oil. 

^ARFIAS,  V.  R. :  The  Effect  of  Igneous  Intrusions  on  the  Accumulation  of 
Oil  in  Northeastern  Mexico.  Jour.  Geology,  vol.  20,  p.  666, 1912. 


SURFACE  INDICATIONS  OF  PETROLEUM         21 

Trinidad  Island  has  one  of  the  largest  deposits  of  asphaltum 
known.  Pitch  Lake,  at  La  Brea,  which  lies  southwest  of  San 
Fernando,  is  137  acres  in  extent  and  has  produced  over  2,000,000 
tons  of  asphalt.  A  heavy  viscous  asphaltic  material  rises  slowly 
into  the  lake.  In  recent  years  an  oil  field  of  considerable  size  has 
been  developed  not  far  from  La  Brea. 

In  a  spring  at  Pechelbronn,  Alsace,  was  discovered  in  1498  an  oil 
which  issued  with  the  water  and  would  burn  in  lamps.  In  1735 
the  outcrop  of  an  oil  sand  was  detected  about  500  feet  from  the 
spring,  and  oil  was  distilled  from  it  in  an  iron  retort.  Subsequently 
this  sand  was  mined  from  a  shaft,  and  still  later  this  field  was 
developed  with  shafts  and  borings. 

In  Galicia  oil  was  collected  at  the  surface  and  in  shallow  wells 
in  the  earliest  historical  era.  The  Boryslaw-Tustanowice  field, 
the  most  productive  in  the  country,  was  noted  for  its  oil  springs 
long  before  deep  exploitation  was  begun.  At  Schodnica  oil  from 
beds  near  the  surface  was  produced  before  deep  drilling  was 
attempted.  In  and  around  Boryslaw  ozokerite  deposits  were 
worked  before  the  field  was  drilled  for  oil.  Most  of  these  deposits 
were  exploited  in  shallow  shafts,  but  later  it  was  found  that  they 
extended  to  very  great  depths  below  the  surface. 

In  Rumania  there  is  a  large  body  of  oil-bearing  strata,  and  at 
many  places  where  they  crop  out  there  are  clear  evidences  of 
petroleum.  In  the  Prahova  and  Bercu  districts  numerous  pits 
were  dug  for  catching  oil.  The  mud  volcanoes  of  the  Berca  and 
Beciu  region  are  famous.  There  for  about  seven  miles  mud  vol- 
canoes, oil  seeps  and  salt  springs  are  closely  spaced.  In  this  region 
at  many  places  oil  is  obtained  from  hand-dug  shafts. 

In  the  foothills  of  the  Caucasus  Mountains  in  Russia  gas  and 
oil  seeps  are  numerous.  The  Balakhany-Sabunchy-Romany  field 
is  an  elongated  dome  where  along  the  main  uplift  there  are  mud 
volcanoes,  many  of  which  spout  mud,  petroleum,  gas,  and  water. 
Of  these  the  Bog-boga  is  over  100  feet  above  the  plateau.  A  short 
distance  from  this  field  is  the  Surakhany  field,  where  gas  was 
obtained  from  seeps  by  the  fire  worshipers,  for  use  in  their  temples 
for  2,500  years.  Off  the  coast  of  Bibi-Eibat,  in  Baku  Bay,  on  the 
Caspian  Sea,  so  much  gas  rises  in  the  water  as  to  agitate  it  vigor- 
ously, and  when  lighted  on  a  calm  day  the  gas  will  burn.1 

The  Grozny  field,  in  the  northern  foothills  of  the  Caucasus,  is 

^THOMPSON,  A.  B.:  Oil-field  Development,  p.  179,  London,  1916. 


22  GEOLOGY  OF  PETROLEUM 

on  an  anticline  6}/£  miles  long.  The  surface  indications  include  oil 
seeps,  and  oil  was  recovered  from  hand-dug  wells  before  the  field 
was  drilled. 

The  Maikop  field,  Kuban,  Russia,  is  300  miles  west  of  Grozny. 
Here  Cretaceous  beds  are.  formed  in  gentle  folds  and  are  uncon- 
formably  overlain  by  Tertiary  beds  that  dip  at  low  angles.  The 
Tertiary  rocks  consist  of  sand  and  shale,  and  where  they  crop  out 
the  sands  are  so  highly  impregnated  with  oil  that  it  oozes  out  when 
the  sand  is  squeezed  in  the  hand.1 

Holy  Island,  in  the  Caspian  Sea  off  the  Apsheron  Peninsula,  is  a 
faulted  dome.  According  to  May,2  there  are  ten  or  twelve  mud 
volcanoes  and  seeps  in  the  faulted  region.  Beds  of  asphalt  and 
small  lakes  of  oil  are  forming  today.  Cheleken  Island,  in  the 
Caspian  Sea,  is  another  faulted  dome,  in  which  hot  salt  springs 
issue  and  deposits  of  ozokerite  are  found  in  faults.  South  of  the 
Caucasus,  in  the  Tiflis  legion,  evidences  of  oil  are  numerous  and 
have  led  to  the  development  -of  a  comparatively  small  oil  field. 
In  the  Ferghana  district,  Turkestan,  oil  seeps  abound. 

In  Egypt,  on  the  coast  of  tne  Red  Sea  near  the  mouth  of  the 
Gulf  of  Suez,  is  the  mountain  known  as  Gebel  Ziet  (oil  mountain), 
called  by  the  Romans,  Mons  Fetrolius.  Here  limestone,  gypsum, 
and  clays  are  impregnated  with  oil  and  gas.  This  material  was 
formerly  used  for  patching  boats  and  wrapping  mummies  by  the 
Egyptians.  Recently  a  considerable  oil  field  has  been  developed 
in  this  region. 

In  Mesopotamia,  in  the  region  of  the  lower  Euphrates  and  Tigris, 
oil  seeps  are  numerous  and  have  furnished  material  for  calking 
boats  and  similar  purposes  since  a  time  long  before  the  Christian 
era.  No  considerable  oil  field  has  been  developed  nearer  than  the 
Persian  field,  to  the  east. 

In  the  Yenangyaung  (earth-oil  creek)  field,  Burma,  India,  on  the 
Irrawady  River,  oil  seeps  in  Tertiary  rocks  are  numerous,  and  the 
Burmese  recovered  considerable  quantities  of  oil  by  sinking  shallow 
shafts.  Mud  dikes  are  found  in  the  Pegu  and  Irrawady  forma- 
tions and  are  supposed  to  fill  the  conduits  through  which  mud 
volcanoes  were  fed  at  a  time  before  the  mud  volcanoes  were  eroded. 
Yenangyat  (earth-oil  place),  Burma,  is  on  an  elongated  dome. 

FRENCH,  R.  H. :  Discussion  of  paper  by  A.  B.  THOMPSON  in  Min.  and  Met. 
Inst.  Trans.,  vol.  20,  p.  247,  1911. 
2Idem,  p.  248. 


SURFACE  INDICATIONS  OF  PETROLEUM         23 

Petroleum  springs  were  long  ago  recognized  there,  and  many  of 
them  are  approximately  at  the  crest  of  the  fold. 

Oil  occurs  in  many  islands  of  the  Oceanica  group.  In  Java  oil 
seeps  are  numerous  along  the  crests  of  folds  which  trend  parallel 
to  the  length  of  the  island.  These  have  led  to  the  development  of 
prolific  oil  fields.  Similar  conditions  are  found  in  Sumatra  and 
Borneo. 

In  the  Philippine  Islands  oil  and  gas  seeps  are  found  in  seven  or 
eight  regions,  though  no  commercial  supplies  have  yet  been  ex- 
ploited. At  Villaba,  at  the  northwest  end  of  Leyte,  considerable 
quantities  of  asphaltum  occur,  probably  along  a  fault  which  cuts 
through  limestone  and  sandstone. 

In  Japan  there  are  many  seeps  in  the  oil  fields,  and  shallow  wells 
were  formerly  dug  to  collect  oil.  ^ 

In  Colombia  oil  seeps  are  numerous  in  many  districts.  Mud 
volcanoes  are  abundant  in  the  Turbaco  field  of  the  Caribbean  dis- 
trict and  in  the  Tubara  field,  20  miles  east  of  Cartagena.  One 
hundred  mud  volcanoes  are  said  to  occur  in  an  area  of  3  acres  near 
developed  oil  wells.  Oil  is  associated  with  the  coal  series  on  the 
Baudo  River  and  may  be  seen  floating  in  the  Andagueda  River,  a 
tributary  of  the  Atrato.  In  the  Magdalena-Santander  district 
there  is  a  large  and  promising  area  where  oil  seeps  are  common. 

In  northern  Argentina  and  Bolivia,  east  of  the  Andes,  oil  springs 
are  abundant  over  a  large  area.  It  is  believed  by  some  that  a 
large  oil  field  will  be  developed  in  this  region. 

In  some  fields  oil  and  gas  seeps  are  lacking.  The  principal  oil 
fields  of  Illinois  show  no  surface  indications,  although  in  one  unim- 
portant field  a  little  oil  seeped  through  a  deep  boring  into  a  coal 
mine.  The  Rivadavia  field,  the  principal  oil-producing  region  in 
Argentina,  was  discovered  by  accident  in  sinking  a  well  for  water. 
The  Roma  gas  field,  Queensland,  Australia,  which  is  not  commer- 
cially productive,  was  discovered  by  drilling  for  water. 

^Oil  Seeps. — Oil  seeps  are  evidences  that  oil  exists  in  the  region 
in  wKich  they  are  found,  though  in  many  regions  that  contain  oil 
seeps  considerable  drilling  has  not  disclosed  commercial  suppliesj— 
for  example,  the  fields  on  the  northwest  coast  of  Newfoundland, 
on  Gaspe  Peninsula,  Quebec,  and  near  Albert,  New  Brunswick. 
Most  of  the  large  oil-producing  regions  of  the  world,  however,  con- 
tain oil  seeps  at  one  place  or  another,  although  numerous  individual 
pools  in  these  regions  do  not  lie  below  the  seeps.  Many  oil  seeps 


24  GEOLOGY  OF  PETROLEUM 

are  associated  with  springs  of  water.  In  some  there  is  merely  a 
slight  iridescent  film  or  *  'rainbow"  of  oil  above  the  water.  Such 
a  film  resembles  somewhat  the  film  of  iron  oxide  that  covers  some 
pools  of  water,  and  iron  oxide  films  have  been  mistaken  for  oil 
films.  The  iron  oxide  film  differs  from  the  oil  film,  however,  in  that 
it  is  brittle  and  will  break  if  the  water  is  agitated,  whereas  the  oil 
film  will  not.  In  many  oil  springs  the  oil  on  the  water  forms  a 
considerable  layer.  At  some  places  it  is  collected  by  laying  a 
blanket  on  the  pool.  The  blanket  absorbs  the  oil  and  is  wrung  out 
and  the  oil  recovered.  In  other  springs  the  oil  is  skimmed  off. 

Oil  Spring,  in  Allegany  County,  New  York,  was  exploited  long 
before  the  Appalachian  oil  field  was  developed.  It  was  described 
by  Benjamin  Silliman1  in  1833  as  follows: 

^*~The  oil  spring  or  fountain  rises  in  the  midst  of  a  marshy  mound; 
it  is  a  muddy  and  dirty  pool,  about  eighteen  feet  in  diameter,  and 
it  is  nearly  circular.  There  is  no  outlet  above  ground — no  stream 
flowing  from  it,  and  it  is  of  course  stagnant  water,  with  no  other 
circulation  than  that  which  springs  from  changes  of  temperature 
and  from  the  gas  and  petroleum  which  are  constantly  rising 
through  the  pool.  The  water  is  covered  with  a  thin  layer  of  the 
petroleum  or  mineral  oil,  giving  it  a  foul  appearance,  as  if  coated 
with  dirty  molasses,  having  a  yellowish-brown  colorj  They  collect 
the  petroleum  by  skimming  it  like  cream  from  a  fmTk  pan.  It  has 
then  a  very  foul  appearance,  like  very  dirty  tar  or  molasses.  Silli- 
man states  that  cattle  like  to  drink  the  water  of  the  spring. 

When  the  amount  of  oil  from  a  well  or  pool  is  very  small,  it  is 
sometimes  difficult  to  ascertain  whether  or  not  a  steady  flow  of  oil 
exists.  Pools  of  water  contaminated  with  oil  that  has  been  used 
to  lubricate  machinery  or  for  other  purposes  have  been  mistaken 
for  oil  springs.  The  petroleum  of  springs  is  generally  heavy, 
because  it  has  suffered  evaporation  or  oxidation  or  both,  and  that 
of  some  springs  resembles  lubricating  oil  in  appearance,  but  often 
tests  or  analyses  will  show  whether  the  oil  of  a  spring  is  in  the 
natural  state  or  whether  it  is  a  product  of  refining. 

A  few  oil  springs  yield  commercial  supplies  of  oil.  One  at 
Urado,  in  the  Uinta  Basin  near  the  Colorado-Utah  line,  has  been 
opened  by  a  short  tunnel  and  supplies  several  barrels  of  high-grade 
lubricating  oil  daily  from  flat-lying  sands.  Many  oil  springs  in 

SILLIMAN,  BENJAMIN:  Notice  of  a  Fountain  of  Petroleum,  Called  the  Oil 
Spring.  Am.  Jour.  Sci.,  vol.  23,  pp.  97-99,  1833  (Silliman's  Journal). 


SURFACE  INDICATIONS  OF  PETROLEUM         25 

Galicia,  Rumania,  Russia,  Burma,  Oceanica,  and  Japan  have  been 
exploited  by  digging  trenches,  shallow  pits,  and  wells  into  which 
the  oil  can  flow.  At  some  places  enormous  quantities  of  oil  flow 
out  at  the  surface.  At  Pitch  Lake,  Trinidad,  enough  has  issued 
to  make  on  drying  over  3,000,000  tons  of  asphalt.  At  Aliat  rail- 
way station  in  the  trans-Caucasus  region,  Russia,  east  of  the  Cas- 
pian Sea,  in  1908  and  1909  so  much  oil  issued  from  fissures  that  it 
formed  large  lakes  inundating  the  railway  tracks.1 

\Oil  Ponds. — At  some  places  oil  has  been  noted  above  the  surface 
of  the  sea,  where  it  has  issued  from  oil  springs  on  the  sea  bottom! 
According  to  Thompson,2  oil  has  been  observed  in  the  Pacific  oft 
the  coast  near  the  oil  fields  of  northern  Peru.  Fenneman3  men- 
tions oil  ponds  in  the  Gulf  of  Mexico  off  the  coast  of  Texas,  where 
ships  find  quiet  water  during  storms.  Off  Galeata  Point,  at  the 
southeast  corner  of  Trinidad,  submarine  eruptions  accompanied 
by  discharges  of  petroleum  and  pitch  are  recorded.4  Holland5 
describes  an  island  off  the  northwest  coast  of  Borneo  that  was  made 
by  an  oil  eruption.  This  island  was  210  by  120  feet  and  was  forty 
feet  high.  Thompson6  states  that  at  many  localities  in  the  Carib- 
bean Sea  off  the  coast  of  Mexico  vast  quantities  of  oil  are  periodi- 
cally ejected,  covering  the  sea  for  miles. 

!  Solid  Bitumens. — Asphaltite  is  a  general  term  applied  to  solid 
asphaltic  hydrocarbons.  Between  oil  and  asphalt  there  are  all 
stages,  grading  from  the  liquid  to  the  solid  state.)  Many  of  the 
solid  hydrocarbons  have  been  described  and  named  as  distinct 
species.  These  include  gilsonite,  uintaite,  elaterite,  wurtzilite, 
albertite,  grahamite,  and  many  others.7  They  vary  greatly  in 

THOMPSON,  A.  B. :  Oil-field  Development.   P.  175,  1916. 

20p.  cit.,  p.  180. 

3FENNEMAN,  N.  M. :  Oil  Fields  of  the  Texas-Louisiana  Gulf  Coastal  Plain. 
U.  S.  Geol.  Survey  Bull  282,  p.  74,  1906. 

THOMPSON,  A.  B.,  op.  cit.,  p.  180. 

'HOLLAND,  T.  H.:  Discussion  of  paper  by  A.  B.  THOMPSON  in  Inst.  Min.  and 
Met.  Trans.,  vol.  20,  p.  233,  1911. 

*0p.  cit.,  p.  179. 

7ELDRiDGE,  G.  H. :  The  Asphalt  and  Bituminous  Rock  Deposits  of  the  United 
States.  U.  S.  Geol.  Survey,  Twenty-second  Ann.  Rept.t  part  1,  p.  220,  1901. 

CLARKE,  F.  W.:  The  Data  of  Geochemistry,  3d  ed.  U.  S.  Geol.  Survey 
Bull.  616,  p.  719,  1916. 

BLAKE,  W.  P.:  Uintaite,  Albertite,  Grahamite,  and  Asphaltum  Described 
and  Compared,  with  Observations  on  Bitumen  and  Its  Compounds.  Am. 
Inst.  Min.  Eng.  Trans.,  vol.  18,  p.  563,  189Q. 


26  GEOLOGY  OF  PETROLEUM 

composition;  most  of  them  are  mixtures  of  hydrocarbons.  Ozoke- 
rite is  largely  paraffin  and  is  an  important  source  of  that  material. 

As  a  rule  the  asphaltites  that  are  found  at  the  surface  contain 
considerable  material  other  than  the  hydrocarbons.  The  asphalt 
of  Pitch  Lake,  Trinidad,  is  about  one-third  sand  and  clay,  one- 
third  water,  and  one-third  bituminous  matter.  Many  asphaltic 
sands  and  bituminous  limestones  carry  from  5  to  20  per  cent  only 
of  bituminous  matter  (p.  27).  Other  bitumens  are  nearly  pure, 
among  them  the  gilsonite  dikes  of  Uinta  Basin,  Utah,  the  gra- 
hamite  dike  of  Ritchie  County,  West  Virginia,  and  the  ozokerite 
deposits  of  Galicia.  Bitumens  that  have  been  deposited  as  dikes, 
especially  those  deposited  as  dikes  in  consolidated  rocks,  are  com- 
monly pure.  These  are  sought  for  fuels,  for  making  varnishes, 
and  for  many  other  purposes. 

Asphalts,  as  already  stated,  are  formed  by  the  inspissation  or 
drying  out  of  petroleum.  They  may  be  regarded  as  the  residual 
products  of  natural  distillation  in  which  the  more  volatile  fluids  are 
generally  scattered.  The  process  is  commonly  attended  by  the 
oxidation  of  certain  constituents,  and  the  oil  becomes  less  readily 
inflammable. 

The  drying  out  of  petroleum  is  undoubtedly  by  far  the  most 
common  method  of  formation  of  bitumens.  Some,  however,  are 
found  in  coal  and  are  believed  to  be  derived  from  vegetable  resins. 
Others  are  associated  with  metallic  ores,  and  it  has  been  suggested 
by  some  writers  that  these  have  originated  at  deep  sources  in  con- 
nection with  volcanic  processes.  Bitumens  are  associated  with 
many  quicksilver  veins  of  California1  and  elsewhere,  and  with  the 
vanadium  veins  of  Minasragra,  Peru.2  As  a  rule  the  deposits  of 
bitumen  in  coal  and  in  metalliferous  veins  are  relatively  small. 
Some  of  the  deposits  derived  from  the  drying  out  of  petroleum  are 
very  large.  The  great  Pitch  Lake  of  Trinidad  has  been  mentioned. 
At  many  other  places  in  Trinidad  there  are  enormous  deposits  of 
asphalt  mingled  with  the  soil.  On  the  mainland  in  Venezuela  the 
Bermudez  deposit  of  asphalt  is  of  the  same  order  of  magnitude. 
The  gilsonite  dikes  of  Utah  are  extensive.  Eldridge  estimated  the 
amount  in  three  of  them  to  be  30,674,613  tons.  At  many  places 


,  G.  F.  :  Geology  of  the  Quicksilver  Deposits  of  the  Pacific  Slope. 
U.  S.  Geol.  Survey  Mon.  13,  pp.  286,  360,  372,  1888. 

2HEWETT,  D.  F.:  Vanadium  Deposits  in  Peru.   Am.  Inst.  Min.  Eng.  Trans., 
vol.  40,  pp.  279-280,  1910. 


SURFACE  INDICATIONS  OF  PETROLEUM         27 

in  California  asphalts  cover  large  areas.  In  Oklahoma,  in  Texas, 
and  in  Kentucky  large  deposits  of  solid  bitumens  have  been  ex- 
ploited. In  some  other  regions  deposits  of  asphalt  are  small. 
Where  they  are  formed  by  leakages  from  outcropping  petroliferous 
strata  they  are  commonly  closely  spaced. 

Bone  Deposits  in  Asphalt. — In  the  petroleum-bearing  area  near 
Los  Angeles,  California,  enormous  deposits  of  impure  asphalt  are 
found  at  the  outcrop  of  an  oil  sand  and  in  the  wash  above  the  sand. 
From  a  pit  dug  in  the  asphalt  numerous  skeletons  of  animals  that 
lived  in  comparatively  recent  times  are  found.  These  remains 
include  the  skeletons  of  saber-tooth  tigers,  deer,  and  other  animals. 
The  deposit  is  a  conglomerate  of  bones  held  together  by  solid  or 
semi-solid  bitumen.  A  little  oil  exudes  in  the  bottom  of  the  pit. 
The  bones  lie  closely  spaced.  Evidently  the  animals  went  to  a 
spring  to  drink  water,  perhaps  somewhat  salty,  and  became 
immersed  in  the  sticky  matter.  Hundreds  of  skeletons  have  been 
taken  from  a  small  pit.1  Thompson  notes  pitch  springs  in  Peru 
with  abundant  bones,  and  he  notes  the  presence  of  similar  deposits 
in  Sviatoi  (Holy  Island),  in  the  Caspian  Sea. 
|  Bituminous  Rocks. — Sandstones  and  limestones  at  many  places 
are  filled  with  dried  or  partly  dried  petroleum.  There  are  all  grad- 
ations between  impure  asphalts  and  bituminous  sandstones.  The 
bituminous  material  in  some  beds  is  formed  from  petroleum  that 
has  risen  in  springs.  An  example  is  that  of  the  "gum  beds"  of  Oil 
Spring,  Ontario.2  In  others  the  bituminous  material  is  that  which 
has  remained  in  the  beds  after  they  have  been  drained  of  oil. 
Washburne3  estimates  that  60  per  cent  of  the  oil  stored  in  sand- 
stone strata  is  ordinarily  removed  from  them  by  wells.  Adsorp- 
tion of  oil  by  sand  grains  is  high,  and  some  of  the  oil  remains  even 
after  repeated  washings  with  water.  If  a  saturated  sand  w^th  20 
per  cent  porosity  is  drained  and  it  retains  40  per  cent' of  its  oil,  the 
oil  would  equal  8  per  cent  of  the  volume  occupied  by  the  sands. 

Probably  the  largest  body  of  bituminous  material  in  the  world 
is  the  deposit  of  "tar  sands"  on  the  Athabasca  River  in  northern 

^LDRIDGE,  G.  H.,  and  ARNOLD,  RALPH:  The  Santa  Clara  Valley,  Puente 
Hills,  and  Los  Angeles  Oil  Districts,  Southern  California.  U.  S  Geol.  Survey 
Bull.  309,  p.  140,  1907. 

2 WILLIAMS,  M.  Y.:  Oil  Fields  of  Southwestern  Ontario.  Canada  Dept. 
Mines  Summary  Rept.,  1918,  part  E,  p.  34,  1919. 

WASHBURNE,  C.  W. :  The  Estimation  of  Oil  Reserves.  Am.  Inst.  Min.  Eng. 
Trans.,  vol.  51,  p.  646,  1916. 


28  GEOLOGY  OF  PETROLEUM 

Alberta,  which  covers  an  area  variously  estimated  at  2,000  to 
10,000  square  miles.  The  sands  are  about  200  feet  thick  and  are 
estimated  to  contain  14  gallons  of  oil  to  the  ton.1  They  are  of 
Cretaceous  age  (Dakota  or  approximately  Dakota)  and  rest  on 
Devonian  limestone.  In  cracks  and  joint  planes  of  the  Devonian 
rock  pitch  has  hardened,  and  Bell2  states  that  the  petroleum  in  the 
sands  has  passed  upward  through  the  Devonian  limestone  at  a 
remote  period. 

Many  petroliferous  strata  contain  at  their  outcrops  a  little 
residual  bituminous  matter  that  is  not  evident  on  inspection  of  the 
outcrop,  although  the  rock  if  broken  under  water  may  yield  an  iri- 
descent film  of  oil. 

TEST  FOR  OIL  IN  ROCKS 

(After  Woodruff) 

1.  Select  a  representative  specimen  of  rock  to  be  tested.     It  is  generally 
advisable  to  obtain  several  samples  as  large  as  one  to  five  pounds  each. 

2.  Break  them  up,  and  thoroughly  mix  the  pieces.     If  the  samples  consist 
of  sand,  mix  the  sand. 

3.  Dry  the  sample  on  a  plate  in  the  sun  or  over  a  radiator.     Do  not  dry  it 
over  a  fire;  to  do  so  may  drive  the  oil  from  the  rock  or  sand. 

4.  Crush  the  sample  to  a  powder.     Mix  the  powder.     Loose  sand  does  not 
need  to  be  crushed. 

5.  Place  about  a  tablespoonful  of  the  sample  in  a  bottle.     Pour  chloroform 
or  carbon  tetrachloride  over  the  sample  until  it  is  thoroughly  saturated  and 
there  is  about  half  a  tablespoonful  of  the  liquid  above  the  crushed  rock  or 
sand.     Cork  the  bottle,  but  not  too  tightly.     Shake  occasionally  for  15  or  20 
minutes. 

6.  Place  a  white  filter  paper  in  a  glass  funnel  over  a  white  dish. 

7.  Pour  the  contents  of  the  bottle  into  the  funnel.     After  the  liquid  has 
passed  through,  place  the  white  dish  in  a  window  where  the  liquid  can  evapo- 
rate. 

8.  Examine  the  filter  paper.     If  the  rock  contains  more  than  a  trace  of  oil, 
there  will  be  a  brown  or  black  ring  on  the  filter  paper. 

9.  After  the  liquid  in  the  dish  has  evaporated,  examine  the  remaining  sub- 
stance.    It  is  the  petroleum  which  was  in  the  rock. 

Apparatus  for  Testing 

One  dinner  plate  on  which  to  dry  specimens. 

Some  means  for  crushing  rock. 

One  or  more  bottles,  4  or  6  ounce  size,  with  corks,  in  which  to  treat  the  rock. 

^ELL,  E.  C. :  Geology  and  History  of  the  Canadian  Field.  Oil  and  Gas  Jour. 
Suppl,  May,  1919,  p.  259. 

2BELL,  ROBERT:  The  Tar  Sands  of  the  Athabasca  River,  Canada.  Am.  Inst. 
Min.  Eng.  Trans.,  vol.  38,  p.  838,  1907. 


SURFACE  INDICATIONS  OF  PETROLEUM         29 

Chloroform  or  carbon  tetrachloride. 

One  glass  funnel  3  or  4  inches  in  diameter. 

Two  dozen  round  filter  papers,  6  inches  in  diameter. 

Two  or  more  white  dishes. 

Bituminous  Dikes. — Bituminous  dikes  are  formed  where  petro- 
leum enters  fissures  and  becomes  hardened  before  it  reaches  the 
surface.  The  process  of  hardening  is  brought  about  by  the  loss  of 
more  volatile  constituents  and  probably  in  some  places  by  oxida- 
tion. Such  dikes,  during  their  formation,  probably  feed  gas  and 
oil  springs  at  the  surface. 

One  of  the  best  known  bituminous  dikes  is  the  albertite  dike  in 


FIG.  5. — Sketch  showing  grahamite  vein  in  Ritchie  County,  West  Virginia. 
(After  Eldridge.) 


New  Brunswick.  In  this  region  Paleozoic  limestone,  shale,  and 
sandstone  are  folded  and  at  some  places  on  edge.  The  Albert 
formation,  which  consists  in  places  of  bituminous  shales  and  sands, 
is  probably  of  Devonian  age,  although  it  has  been  placed  by  some 
in  the  lower  Carboniferous.  It  yields  as  much  as  50  gallons  of 
shale  oil  to  the  ton  and  has  been  distilled  on  a  commercial  scale. 
Surficial  indications  of  oil  are  widely  distributed  in  this  region. 
The  Albert  shale  under  cover  of  overlying  rocks  has  been  pene- 
trated by  the  drill  and  jrielded  considerable  quantities  of  gas  and 
some  oil.  The  only  large  albertite  dike  is  that  at  the  Albert 


30  GEOLOGY  OF  PETROLEUM 

mine.1  This  dike  was  worked  to  depths  of  1,100  feet  or  more  and 
for  half  a  mile  along  the  strike.  At  places  it  is  15  feet  wide  and 
sends  out  apophyses  into  the  country  rock.  It  is  nearly  straight, 
stands  approximately  vertical,  and  follows  the  general  direction  of 
an  anticlinal  axis.  It  has  yielded  over  200,000  tons  of  albertite. 

In  Ritchie  County,  West  Virginia,  there  is  a  dike  of  grahamite," 
much  like  the  albertite  dike  of  Nova  Scotia.  This  dike  (Fig.  5)  is 
nearly  a  mile  long  and  about  5  feet  wide  for  the  most  part,  thin- 
ning out  to  a  few  inches  at  the  ends.  It  stands  nearly  vertical. 
The  fissure  that  is  filled  with  grahamite,  according  to  Fontaine,  is 
a  zone  of  fracturing,  probably  one  of  slight  displacement.  As 
noted  by  White3  the  fissure  strikes  almost  at  right  angles  to  the 
great  Burning  Springs- Volcano-Eureka  anticline,  which  produces 
oil  west  of  the  deposit.  The  fissure  is  supposed  to  have  been  made 
by  tension  during  the  formation  of  the  anticline  and  was  rilled  with 
petroleum  largely  from  the  Cairo  sand,  which  lies  at  a  depth  of 
1,530  feet4  and  is  the  main  producing  rock  of  this  region.  The 
Big  Injun  sand  below,  at  a  depth  of  1,652  feet,  also  may  have  con- 
tributed petroleum.  The  oil  filling  the  fissure,  according  to  White, 
was  gradually  converted  by  oxidation  and  other  processes  into 
grahamite. 

Grahamite  dikes  are  found  also  in  south-central  Oklahoma. 

In  the  Uinta  Basin,  Utah,  lower  Tertiary  beds  consisting  of 
shales,  sandstones,  and  limestones  of  the  Wasatch  and  Green  River 
formations  dip  northward  at  low  angles  toward  the  Uinta  Moun- 
tains.5 The  section  includes  several  hundred  feet  of  the  Green 
River  oil  shales,  which  on  heating  will  yield  large  amounts  of  shale 

:ELLS,  R.  W. :  The  Bituminous  or  Oil  Shales  of  New  Brunswick  and  Nova 
Scotia.  Part  2,  p.  9,  Canada  Geol.  Survey,  1909. 

YOUNG,  G  A.:  Twelfth  Internat.  Geol.  Congress  Guide  Book  No.  1,  part  2, 
pp.  366-367,  1913. 

CLAPP,  F.  G.,  and  others:  Petroleum  and  Natural  Gas  Resources  of  Canada 
Part  2,  p.  50,  Canada  Dept  Mines,  Mines,  Branch,  1915. 

FONTAINE,  W.  M. :  Notes  on  the  West  Virginia  Asphaltum  Deposit.  Am. 
Jour.  Sci.,  3d  ser.,  vol.  6,  p.  409,  1873. 

3 WHITE,  I.  C. :  Origin  of  Grahamite.  Geol.  Soc.  America  Bull.,  vol.  10, 
p.  278,  1899. 

4ELDRiDGE,  G.  H. :  The  Asphalts  and  Bituminous  Rock  Deposits  of  the 
United  States  U.  S.  Geol.  Survey,  Twenty-second  Ann.  Rept.,  part  1,  p.  235, 
1901. 

5WiNCHESTER,  D.  E. :  Oil  Shales  of  the  Uinta  Basin.  U.  S.  Geol.  Survey 
Bull.  691,  p.  27,  1919. 


SURFACE  INDICATIONS  OF  PETROLEUM          31 


oil.  In  this  region  dike  hydrocarbons  are  developed  in  great 
variety.  Asphaltic  dikes  consisting  of  gilsonite  (Fig.  6),elaterite, 
tabbyite,  albertite,  wurtzilite,  and  nigrite  are  developed  and  also 
dikes  of  paraffin,  ozokerite.  The  asphaltic  dikes  are  found  both 
above  and.  below  the  oil-shale  formation,  and  the  ozokerite  dikes 
below  it.  The  gilsonite  dikes  are  very  large  and  extend  for  many 
miles  along  the  strike.  Eldridge1  suggested  that  the  hydrocarbons 
that  filled  the  dikes  were  derived  from  Cre- 
taceous shales  and  that  they  came  from  be- 
low under  pressure.  Winchester2,  however, 
regards  as  plausible  the  hypothesis  that  the 
Green  River  oil  shale  supplied  the  material 
for  all  the  bituminous  dikes  of  the  Uinta 
Basin,  as  well  as  the  asphaltic  material  that 
saturates  certain  sandstones  in  the  region. 

Deposits  of  solid  bitumen  in  the  form  of 
dikes  are  commonly  associated  with  gas. 
In  the  ozokerite  mines  of  Galicia  strong  cur- 
rents of  air  are  blown  into  the  galleries  to  re- 
move the  gas  and  prevent  injury  to  the 
miners.  In  the  Old  Black  Dragon  gilsonite 
mine,  near  Black  Dragon  station,  Utah,  no 
explosives  are  used,  and  possession  of 
matches  in  the  mines  is  prohibited  under 
threat  of  dismissal.  Electric  lights  only  are 
permitted.  A  disastrous  explosion  which 
caused  the  death  of  several  men  is  supposed 
to  have  resulted  from  the  striking  of  a 
match  by  a  miner  in  defiance  of  orders.  The 
fire  which  ensued  melted  some  of  the  gilson- 
ite and  caused  it  to  run  down  into  the  old 
slopes,  so  that  after  the  mine  was  reopened  gilsonite  was  being 
mined  in  the  same  places  from  which  gilsonite  had  been  removed 
before  the  explosion. 

Ozokerite,  or  mineral  wax,  is  a  native  bitumen  with  a  paraffin 
base.  It  is  essentially  paraffin.  It  is  found  in  Galicia,  in  Eng- 
land, on  Cheleken  Island  in  the  Caspian  Sea,  in  the  Salt  Creek 
region  of  Wyoming,  and  in  the  Uinta  Basin  in  Utah.  It  is  sup- 

I0p.  tit.,  p.  351. 
Z9p.  tit.,  p.  49. 


0         4         8  feet 
Scale 

FIG.  6.— Sketch 
of  gilsonite  dike, 
Duchesne  Mine, 
Uinta  Basin, 
Utah.  (After  El- 
dridge.') The  gilson- 
ite is  black,  a,  sand- 
stone walls  of  dike; 
6,  fragments  of 
sandstone  in  dike. 


32 


GEOLOGY  OF  PETROLEUM 


posed  to  be  formed  by  the  drying  out  of  paraffin  oil.  Considering 
its  origin,  its  occurrence  at  depths  of  nearly  2,000  feet  at  Boryslaw, 
Galicia,  is  noteworthy.1  (Fig.  7.) 

In  the  Salt  Creek  region,  Wyoming,  according  to  Wegemann,2 
ozokerite  is  associated  with  calcite,  which  fills  all  fault  fissures  at 
the  surface.  It  is  produced  by  the  evaporation  of  oil  that  has 
risen  in  these  fissures  and  long  remained  in  them.  The  deposits  of 
ozokerite  appear  to  be  confined  to  the  dome  above  the  oil  pool  and 
are  not  found  in  the  adjoining  synclines,  in  which  shale  oil  is 


Meters  Sw 


I 1  Miocene  salt  shale  (';V;..:1  Allimum 

Dobrotow  sandstone  and  shale*  K%%4  Oil 

f    Upper 

Dobrotow  conglomerate  joilgocene  f^j>|  Ozokerite 

]  Menllitic  shale  (lower  Oligocene  )  ft      Ozokerite  mine 

™«""»oll  Dry  Well 

FIG.  7. — Profile  through  Boryslaw  oil  field,  Galicia,  showing  ozokerite  veins 
above  an  anticline.  Horizontal  and  vertical  scales  are  the  same.  (After  Zitber.) 

encountered.    This  relation  is  suggested  also  by  the  section  in 
Fig.  7. 

Many  natural  oils  carry  paraffin  in  solution.  When  these  issue 
in  wells,  owing  to  relief  of  pressure  and  consequent  decrease  in 
temperature,  some  of  them  deposit  paraffin  in  the  bores.  Prob- 
ably some  ozokerite  dikes  are  similarly  formed  where  oil  escapes 
through  fissures. 

'ZuBER,  RUDOLPH:  Die  Geologische  Verhaltnisse  von  Boryslaw  in  Ostga- 
lizien.  Zeitschr.  prakt.  Geologic,  1904,  pp.  41-48. 

WEGEMANN,  C.  H. :  The  Salt  Creek  Oil  Field,  Wyoming.  U  S.  Geol. 
Survey  Bull.  670,  p.  36,  1911. 


SURFACE  INDICATIONS  OF  PETROLEUM         33 

Gas  Seeps. — Gas  accompanies  the  oil  that  issues  at  many  oil 
springs.  There  are  also  many  gas  seeps  where  no  oil  issues. 
Because  the  gas  is  colorless  and  some  of  it  odorless,  gas  seeps  are 
not  so  easily  recognized  as  oil  seeps.  Many  of  them  have  been 
recognized  where  the  gas  issues  as  bubbles  in  pools  of  water  or  by 
explosions  of  the  gas  resulting  from  accidental  ignition.  Where 
the  gas  is  under  pressure  and  the  seep  is  in  a  sand  or  soft  sandy 
earth,  the  movements  of  the  sandy  or  clay  particles  may  lead  to 
the  discovery  of  gas.  The  issue  of  gas  under  pressure  may  build 
up  small  "pimples,"  mounds,  or  mud  volcanoes  on  the  surface, 
which  are  easily  recognized.  Where  heavy,  lethal  gases  issue  in 
depressions,  animals  exposed  to  them  are  killed,  and  the  remains 
mark  the  places  of  accumulation. 

The  gases  that  issue  at  the  surface  of  the  earth  include  chlorine, 
nitrogen,  carbon  dioxide,  carbon  monoxide  sulphurous  com- 
pounds, methane,  and  other  hydrocarbons.  Chlorine,  nitrogen, 
and  carbon  dioxide  have  little  significance  as  surficial  indications 
of  petroleum.  They  are  not  inflammable,  and  they  issue  in  regions 
where  volcanic  processes  are  active  or  have  recently  been  active, 
and  elsewhere.  Carbon  monoxide  is  not  ordinarily  abundant  in 
gas  seeps,  although  a  little  may  be  present  associated  with  other 
gases.  Carbon  monoxide  and  methane  are  the  "fire  damp"  of 
coal  mines. 

Carbon  dioxide,  carbon  monoxide,  and  gases  other  than  the 
hydrocarbon  gases  are  found  under  many  geologic  conditions. 
They  are  comparatively  rare  in  considerable  amounts  in  association 
with  petroleum,  although  one  or  more  are  present  in  some  petro- 
leum gases,  mixed  as  a  rule  with  much  larger  quantities  of  methane. 
The  hydrocarbon  gases  are  commonly  associated  with  oil  and  are 
more  significant  as  indications  of  oil  than  carbon  dioxide  and  car- 
bon monoxide.  Helium  is  found  in  some  natural  gases  (p.  82). 

The  most  common  constituent  of  natural  gases  is  methane. 
Methane  gas,  however,  is  not  all  associated  with  petroleum  de- 
posits. It  is  "marsh  gas,"  which  forms  in  peat  bogs  or  anywhere 
that  vegetation  is  decaying.  The  "will-o'-the-wisp"  of  the  marshes 
and  swamps  is  burning  methane.  It  occurs  in  swamp  deposits 
that  are  buried  below  glacial  lacustrine  clays  in  Minnesota  and 
bordering  States.  In  many  fields,  however,  as  stated  above, 
methane  is  associated  with  petroleum.  Commonly  the  methane 
contains  also  small  amounts  of  other  gases.  In  some  fields  ethane, 


34  GEOLOGY  OF  PETROLEUM 

propane,  and  butane  are  associated  with  methane.  These  and 
heavier  hydrocarbon  gases  are  generally  regarded  as  evidence  that 
the  gas  is  petroleum  gas — that  is,  that  it  is  associated  with  oil — 
and  if  the  structure  of  the  beds  is  favorable  their  presence  warrants 
drilling  for  oil  at  a  structurally  lower  point,  below  the  gas  reservoir. 
Some  analyses  of  gases  are  given  below. 


ANALYSES  OF  GAS  OF  TEXAS  AND  LOUISIANA  FIELDS 
(By  Bureau  of  Mines.    From  U.  S.  Geol.  Survey  Bull.  661,  p..  239,  1918.) 


l 

2 

3 

4 

5 

6 

7 

Carbon  dioxide  (CO2)  .... 
Oxygen  (O2)  .  . 

1.7 
1.1 

Trace 
0.0 

0.0 
0.0 

1.0 
0.0 

7.30 
0.0 

0.2 
0.1 

0.2 
0.1 

Methane  (CH4)  

91.9 

98.5 

96.5 

98.5 

54.5 

52.7 

92.4 

Nitrogen  (N2)  ... 

5.3 

1.5 

3.5 

0.5 

38.2 

37.8 

3.9 

Ethane  (C  H6) 

9  3 

3  4 

Specific   gravity   deter- 
mined. .  . 

100.0 
0.60 

100.0 
0.56 

100.0 
0.57 

100.0 
0.58 

100.0 
0.79 

100.0 
0.78 

100.0 
0.60 

Specific  gravity  calculated 
Heating  value,  in  British 
thermal  units,    at  deg. 
C.                  . 

979 

1,052 

0.57 
1,027 

0.57 
1,030 

580 

755 

0.59 

1.  Well  No.  1  on  Mackey  lease,  near  Corsicana,  Texas. 

2.  Well  on  Anglin  lease  of  Robinson  Oil  &  Gas  Co.,  Mexia-Groesbeck  field,  Texas.    U.  S. 
Geol.  Survey  Bull,  629,  p.  102,  1916. 

3.  Well  on  L.  B.  Phillips  lease  of  Southwestern  Gas  &  Electric  Co.,  10  miles  west  of  Shreve- 
port,  Louisiana.     Depth  1,000  feet. 

4.  Edwards  well  No.  1  of  Southern  Oil  &  Gas  Co.,  sec.  23,  T.  21  N,.  R.  11  W.,  Caddo  field, 
near  Vivian,  Louisiana.     Depth  1,040  feet. 

5.  Swamp  gas. 

6.  Beatty  well  No.  1,  Petrolia  field,  Texas.     U.  S.  Geol.  Survey  Bull,  629,  p.  41,  1916. 

7.  P.  H.  Youree  well  No.  3  of  Gulf  Refining  Co.  of  Louisiana,  sec.  33,  T.  17  N.,  R.  14  W., 
louth  of  Shreveport,  Louisiana. 

The  presence  of  ethane,  propane,  and  butane  in  gas  is  generally 
regarded  as  a  favorable  indication  of  petroleum,  because  these 
substances  are  found  in  a  great  many  gases  that  are  associated  with 
oil.  Nevertheless,  their  presence  is  not  an  infallible  indication. 
One  or  more  of  the  hydrocarbon  gases  heavier  than  methane  were 
found  in  a  sample  of  natural  gas  collected  in  1917  in  a  glacial-lake 
deposit  that  is  covered  with  lacustrine  clay  in  southern  Minnesota. 
On  the  other  hand,  a  gas  from  the  Edwards  well  (see  table  above), 


SURFACE  INDICATIONS  OF  PETROLEUM         35 

in  the  Caddo  field,  Louisiana,1  showed  on  analysis  no  hydrocarbon 
except  methane,  although  the  sand  that  yielded  the  gas  contains 
oil  in  the  same  part  of  the  field  where  the  gas  sample  was  taken. 

Natural  gas  carries  gasoline  vapors  much  as  air  carries  water 
vapor.  Gas  under  great  pressure  is  less  likely  to  carry  the  gasoline 
vapors  than  gas  under  less  pressure.  When  a  boring  penetrates 
a  reservoir  containing  oil  and  gas  under  great  pressure,  the  gas 
immediately  expands  and  moves  toward  the  hole,  carrying  the  oil 
with  it.  As  there  is  less  resistance  to  the  movement  of  the  gas  it 
moves  faster  and  is  exhausted  first.  When  the  pressure  is  high 
the  dry  gases  absorbed  in  the  oil  are  liberated,  but  as  pressure 
decreases 2  the  wet  gases  liquified  and  dissolved  in  the  oil  are  also 
released.  A  dry  gas  issuing  under  great  pressure  is  more  likely 
to  be  associated  with  oil  than  a  dry  gas  issuing  under  low  pressure. 

Gas,  like  oil,  issues  both  on  land  and  sea.  The  seep  on  the 
Caspian  Sea  off  Bibi-Eibat  has  been  mentioned.  Near  Holy 
Island,  also  in  the  Caspian  Sea,  and  off  the  coast  of  Peru,  as 
observed  by  Thompson,3  gas  exuded  beneath  the  sea. 

Sulphurous  gases  and  sulphur  are  associated  with  many  petro- 
leums and  in  smaller  proportions  with  some  natural  inflammable 
gases.  The  sulphur  gases  include  sulphur  dioxide  and  hydrogen 
sulphide,  both  of  which  are  easily  detected  by  their  odor.  The 
gases  accompanying  the  oil  at  Spindletop  field,  near  Beaumont, 
Texas,  were  poisonous,  possibly  owing  to  the  presence  of  sulphur 
compounds.  These  gases  deposited  sulphur  on  the  Spindletop 
dome,  and  it  was  the  occurrence  of  such  deposits  that  led  to  the 
drilling  of  this  field  in  a  search  for  commercial  deposits  of  sulphur. 4 

Sulphur  gases  are  found  at  the  surface  of  many  of  the  salt-dome 
deposits  of  Texas  and  Louisiana  (p.  365).  Because -sulphur,  hydro- 
gen sulphide,  and  sulphur  dioxide  are  widely  dispersed  in  nature 
and  occur  in  places  far  removed  from  petroleum  deposits,  they  are 
generally  of  uncertain  value  as  indications  of  oil,  although  in  some 
small  areas  their  presence  is  regarded  as  significant. 

JMATSON,  G.  C.,  and  HOPKINS,  O.  B.:  The  Corsicana  Oil  and  Gas  Field, 
Texas.  U.  S.  Geol.  Survey  Bull  661,  p.  239,  1918 

2LEWis,  J.  O. :  Methods  for  Increasing  the  Recovery  from  Oil  Sands.  U.  S. 
Bur.  Mines  Bull,  148,  p.  20,  1917. 

THOMPSON,  A.  B. :  Oil-field  Development,  p.  180,  London,  1916. 

4LucAS,  A.  F. :  Principles  and  Problems  of  Oil  Prospecting  in  the  Gulf  Coast 
Country  (discussion).  Am.  Inst.  Min.  Eng.  Trans.,  vol.  59,  p.  470,  1917. 


36  GEOLOGY  OF  PETROLEUM  ' 

Paraffin  Dirt. — The  so-called  paraffin  dirt  of  the  Gulf  coast  oil 
fields1  has  been  considered  an  indication  of  the  presence  of  oil  and 
gas,  and  wells  have  been  brought  in  on  the  basis  of  such  evidence. 
Its  association  with  oil  and  gas  was  first  pointed  out  by  Lee  Hager. 

The  term  "paraffin  dirt"  has  been  applied  to  peaty,  clay  soils 
with  a  peculiar  texture,  which  has  been  described  as  "curdy"  or 
"rubbery."  When  moist,  the  material  breaks  much  after  the 
fashion  of  "green"  cheese.  It  is  rubbery  under  compression  but 
does  not  resemble  rubber  in  tenacity  or  cohesion.  In  the  field  it 
resembles  "art  gum."  When  dry,  the  material  ranges  from  hard 
clods  to  a  horny  mass. 

The  moist  material  ranges  in  color  from  dark  brown  in  the  speci- 
mens rich  in  organic  matter  to  grayish  in  specimens  containing 
more  inorganic  matter.  It  is  readily  attacked  by  molds.  It  has 
a  characteristic  "swampy"  or  "mucky"  odor  when  wet. 

Brokaw  analyzed  a  sample  taken  1  mile  north  of  Spanish  Lake, 
St.  Martin  Parish,  Louisiana,  near  a  test  well;  another  near  the 
discovery  well  in  the  New  Iberia  oil  field,  Iberia  Parish;  one  from 
Lake  Dauterive,  St.  Martin  Parish;  and  another  near  the  discovery 
well  in  St.  Martin  Parish.  He  showed  that  the  place  of  paraffin 
dirt  among  the  evidences  of  oil  and  gas  rests  on  the  possibility  that 
it  may  indicate  gas-saturated  soils  in  which  gas  inhibits  oxidation, 
and  obviously  such  soils  are  present  in  the  vicinity  of  gas  seeps. 
It  does  not  necessarily  follow  that  every  gas  seep  is  accompanied 
by  paraffin  dirt,  nor  is  paraffin  dirt  an  infallible  sign  of  a  gas  seep. 
Most  "paraffin  dirt"  probably  contains  no  paraffin. 

Mud  Volcanoes. — Gas  issuing  at  the  surface  may  carry  with  it 
particles  of  sand  and  clay  which  are  deposited  at  the  place  of  issue. 
Continuation  of  the  process  will  build  up  a  "pimple,"  mound,  or 
cone.  The  process  goes  on  generally  in  unconsolidated  rocks, 
especially  in  the  presence  of  water.  If  the  wet  clay  or  mud  seals 
over  the  place  of  issue  gas  accumulates  under  pressure,  and  when 
the  pressure  is  sufficient  it  blows  off  the  seal  with  violence,  imitat- 
ing on  a  small  scale  the  eruption  of  a  volcano.  In  arid  countries 
these  mounds  are  built  to  considerable  heights.  The  Bog-Boga 
mud  volcano,  in  the  principal  oil  district  of  the  Baku  region, 
Russia,  is  more  than  100  feet  above  the  plateau  on  which  it  stands 
and  forms  one  of  the  high  features  of  the  landscape.  (See  p.  540. ) 

BROKAW,  A.  D. :  An  Interpretation  of  the  So-called  Paraffin  Dirt  of  the  Gulf 
Coast  Oil  Fields.  Am.  Inst.  Min.  Eng.  Bull.  136,  pp.  947-950,  1918. 


SURFACE  INDICATIONS  OF  PETROLEUM         37 

In  many  Tertiary  oil  fields  where  the  rocks  are  unconsolidated  mud 
volcanoes  are  numerous.  On  the  Taman  and  Kertch  peninsulas, 
north  of  the  Black  Sea,  there  are  many  mud  volcanoes,  and  great 
streams  of  mud  flow  down  their  sides.  Several  mud  volcanoes  are 
present  on  the  shore  of  the  Caspian  Sea  southwest  of  Baku,  near 
the  Bibi-Eibat  oil  field.  They  are  reported  also  on  Cheleken 
Island,  and  at  Napthun,  east  of  the  Caspian  Sea.  They  occur  in 
Rumania  (p.  532)  and  are  numerous  on  the  Arakan  Islands,  off  the 
west  coast  of  Burma,  and  on  Cape  Negrais,  in  southwestern 
Burma.1  They  are  found  also  in  Borneo,  Sumatra,  Trinidad  and 
Colombia.  At  many  places  in  Rumania,  Russia,  Borneo,  and 
Sumatra,  they  are  on  anticlines  in  Tertiary  rocks  that  have 
yielded  oil. 

Mud  volcanoes,  like  seeps  of  oil  and  gas,  have  been  known  to 
rise  from  the  seai  bottom.  In  1897  during  an  earthquake  a  great 
mud  volcano  rose  off  the  Klias  peninsula,  Borneo.  The  material 
ejected  formed  an  island  750  feet  long  and  420  feet  wide.  Stigand 
states2  that  this  island  was  50  to  60  feet  high  and  eventually 
became  joined  to  the  mainland.  Thompson  records  a  volcano 
near  the  Arakan  Islands,  off  the  coast  of  Burma,  which  in  1907 
threw  out  enough  muddy  material  to  make  an  island  1,200  feet 
long,  600  feet  wide,  and  20  feet  high.  The  material  had  a  temper- 
ature of  148°  F. 3  Off  Erin,  on  the  south  coast  of  Trinidad,  in  1911 
masses  of  hot  mud  with  much  gas  were  thrown  out  from  the  sea 
and  formed  an  island  of  2^2  acres,  14  feet  high.  This  eruption, 
according  to  Thompson,  occurred  above  a  submarine  anticline. 

There  are  no  typical  mud  volcanoes  in  the  United  States.  Pos- 
sibly some  of  the  mounds  of  the  Gulf  coast  region  of  Texas  and 
Louisiana  have  been  formed  by  processes  nearly  related  to  those 
which  operate  to  form  mud  volcanoes.  Features  like  small  mud 
volcanoes  appear  at  the  surface  in  the  Vale  region  of  Oregon  and 
Idaho.  In  the  Caddo  district  of  Louisiana  small  pimply  elevations 
have  been  noted,  but  these,  according  to  Matson,  are  probably  the 
work  of  ants. 

Somewhat  similar  in  origin  to  mud  volcanoes  are  the  sand  heaps 
that  accumulate  at  the  casing  heads  of  some  gushers  drilled  in 

^ERGHAUS,  H. :  Atlas  der  Geologic,  Gotha,  1892. 

STIGAND,  J  A. :  Discussion  of  paper  by  A.  B  THOMPSON  in  Inst.  Min.  and 
Met.  Trans.,  vol.  20,  p.  262,  London,  1911. 

3THOMP80N,  A.  B. :  Oil-field  Development.    P.  184,  1916 


38  GEOLOGY  OF  PETROLEUM 

loose  sand.  At  some  of  the  wells  in  California  the  engine  houses 
and  the  lower  parts  of  derricks  have  been  thus  completely  buried. 
In  some  wells  in  the  Sunset  field,  California,  two-thirds  of  the  total 
yield  is  sand.  One  well  produced  nearly  110,000  cubic  feet  of  sand 
in  two  years.  Some  pumping  wells  in  the  North  Midway  field, 
California,  produce  sand  at  the  rate  of  over  200,000  cubic  feet 
a  year.1 

Describing  the  sand  masses  produced  by  wells  in  Russia,  Thomp- 
son2 says  that  the  oil  from  fountains  is  commonly  accompanied  by 
an  equal  bulk  of  sand,  large  numbers  of  stones,  and  millions  of 
cubic  feet  of  gas  which  becomes  disengaged  from  the  oil  on  its  exit 
from  the  tube.  A  Bibi-Eibat  well  spouted  10,000  tons  of  oil  and 
10,000  tons  of  sand  in  a  day  and  in  a  few  weeks  yielded  1,700,000 
cubic  feet  (85,000  tons)  of  sand,  which  is  enough  to  cover  an  acre 
to  a  depth  of  nearly  40  feet. 

Mud  Dikes. — Mud  dikes  that  cut  across  the  strata  are  found  in 
some  oil  fields.  They  are  supposed  to  have  filled  the  vents  through 
which  gas  issued  to  form  gas  seeps  or  mud  volcanoes.  Such  dikes 
are  found  in  Burma  in  the  Yenangyat3  and  Yenangyaung  fields. 
What  are  undoubtedly  mud  dikes  occur  in  the  Huron  shales  of  the 
gas  field  around  Cleveland,  Ohio.  Dikes  are  formed  also  by  clay 
squeezed  into  fissures. 

Oil  Shales. — As  oil  shales  are  commonly  the  original  sources  of 
petroleum  and  gas,  their  presence  is  usually  regarded  as  a  favorable 
indication.  McCoy 4  says  that  petroleum  shales  are  always  present 
in  the  petroliferous  series  that  are  exploited  in  the  Oklahoma- 
Kansas  field.  From  such  a  shale,  under  great  compression,  he 
extracted  a  little  oil.  Winchester5  suggests  the  Green  River  oil 
shales  as  sources  of  the  great  gilsonite  veins  and  other  solid  hydro- 
carbons that  are  abundant  in  the  Uinta  Basin,  Utah.  Oil  is 
extracted  commercially  from  the  oil  shales  of  the  West  and  Mid- 

XKOBBE,  W.  H. :  Problems  Connected  with  the  Recovery  of  Petroleum  from 
Unconsolidated  Sands.  Am.  Inst.  Min.  Eng.  Trans.,  vol.  1,  56,  pp.  799-822, 
1916. 

THOMPSON,  A.  B. :  The  Oil  Fields  of  Russia.    Pp.  52-53,  London,  1908. 

SPASCOE,  E.  H. :  The  Oil  Fields  of  Burma.  India  Geol.  Survey  Mem.,  vol. 
40,  part  1,  pp.  72-73,  1912. 

4McCoY,  A.  W. :  Notes  on  Principles  of  Oil  Accumulation.  Jour.  Geology, 
vol  27,  pp.  252-262,  1919. 

5WiNCHESTER,  D.  E. :  Oil  Shale  of  the  Uinta  Basin,  Northeastern  Utah. 
U.  S.  Geol.  Survey  Bull.  691,  pp.  27-55,  1919. 


SURFACE  INDICATIONS  OF  PETROLEUM         39 

lothian  districts,  Scotland,1  and  elaborate  attempts  have  been 
made  to  extract  oil  profitably  from  the  kerosene  shales  of  New 
South  Wales.  Some  oil  shales  approach  coal  in  carbon  content  and 
yield  80  to  120  gallons  of  oil  to  the  ton.2  The -oil  shales  of  the 
Albert  series,  at  Albert,  New  Brunswick,  which  were  once  exploited 
for  oil,  are  reported  to  carry  50  gallons  to  the  ton. 

Burnt  Shales. — In  California  the  Monterey  shale,  which  accord- 
ing to  Arnold  has  supplied  the  bulk  of  the  material  from  which  the 
oil  of  that  region  was  derived,  is  burnt  red  at  many  places,  some  of 
them  in  the  Santa  Clara  district.3  The  alteration  has  taken  place 
at  depths  far  below  the  usual  depths  of  oxidation.  In  Trinidad 
red  shale  is  found  at  many  places.  This  is  presumably  a  clay 
burnt  hard  by  the  oxidation  of  the  petroliferous  material  it  con- 
tained. The  burnt  clay  is  termed  porcelainite._4  Here,  as  in  Cali- 
fornia, slow  combustion  has  evidently^penetrated  to  depths  beyond 
those  to  which  air  can  easily  penetrate.  Eldridge  and  Arnold  sug- 
gest that  the  changes  in  California  are  brought  about  by  spontan- 
eous combustion.  At  Burnt  Hill,  Barbados,5  a  bituminous  shale 
by  slow  combustion  has  been  converted  into  a  hard,  bricklike  rock. 
Thompson  mentions  places  on  the  Yorkshire  and  Dorsetshire 
coasts  of  England  where  Lias  and  Kimmeridge  bituminous  clays 
which  exude  oil,  ignite  and  burn  for  considerable  periods. 

Salt- Water  Seeps. — Salt  water  is  associated  with  petroleum  i 
practically  every  large  oil-producing  region  in  the  world.  (Se^ 
p.  48.)  The  only  places  known  to  me  where  oil  is  associated 
with  water  that  is  fresh  or  nearly  fresh,  are  in  the  Rocky  Mountain 
region  of  the  United  States,  where  in  several  fields  the  water  that 
floats  the  oil  is  evidently  mingling  with  circulating  ground  water 
and  has  been  thereby  diluted.  Salt  seeps  are  found  in  many  oil 
fields.  Many  salt  licks,  or  places  where  animals  congregate  to  lick 
the  salt  from  the  earth  or  rocks,  are  formed  of  drying  brine.  Where 
the  brine  is  associated  with  oil  the  animals'  feet  become  oil  soaked, 
and  it  is  said  that  oil  seeps  have  been  discovered  by  men  observing 

^TETTART,  D.  R.:  The  Oil  Shales  of  the  Lothians,  2d  ed.,  part  3.  Scotland 
Geol.  Survey  Mem.,  1912. 

THOMPSON,  A.  B.:  Oil-field  Development.    P.  205,  1916. 

3ELDRiDGE,  G  H.,  and  ARNOLD,  RALPH:  The  Santa  Clara  Valley  Oil  Dis- 
trict, Southern  California.  U.  S.  Geol.  Survey  Bull.  309,  p.  22,  1907. 

4WALL,  G.  P.,  and  SAWKINS,  J.  G. :  Report  on  the  Geology  of  Trinidad. 
Part  1,  p.  50,  West  Indian  Survey,  1860. 

THOMPSON,  A.  B  :  Oil-field  Development.    P.  195,  1916. 


40  GEOLOGY  OF  PETROLEUM 

oil  on  the  feet  of  pigs  that  had  returned  to  farmhouses  from  their 
range.  Large  quantities  of  bones  are  found  in  some  such  places. 
These  are  evidently  the  remains  of  animals  that  drank  at  springs 
which  possibly  were  salty. 

Brine  and  rock  salt  are  among  the  most  widely  distributed 
materials  in  the  earth  and  occur  at  many  places  far  removed  from 
oil  fields.  The  presence  of  salt  water  may  suggest  the  possibility 
of  petroliferous  strata,  but  it  has  no  certain  significance,  as  many 
oil  pools  have  been  found  where  no  salt  springs  issue  and  many 
salt  springs  issue  at  places  remote  from  oil  fields. 

Sulphur  and  Sulphur  Compounds. — Sulphur  or  sulphur  com- 
pounds are  found  in  the  petroleum  of  many  fields  and  in  the  salt 
water  that  is  associated  with  the  petroleum.  Probably  some  of 
the  sulphur  associated  with  petroleum  has  been  derived  from  the 
plants  and  bodies  of  animals  that  supplied  the  material  from  which 
the  oil  and  gas  have  been  derived.  If,  as  is  supposed  by  many, 
petroleum  bacteria  convert  organic  material  to  oil  and  gas,  sulphur 
bacteria,  which,  like  the  so-called  petroleum  bacteria,  are  anae- 
robic, probably  work  under  similar  conditions  to  convert  sulphates 
to  sulphur  and  its  unoxidized  compounds.  Sea  water  that  is 
buried  with  the  sediments  that  yield  oil  is  probably  the  principal 
source  of  the  sulphur. 

Sulphurous  gases  have  been  mentioned  (p.  35).  Some  of  them 
deposit  native  sulphur  and  on  oxidation  yield  sulphuric  acid.  In 
the  Spindletop  oil  field  of  the  Gulf  coast  region,  sulphur  was  found 
in  the  soil,  and  the  discovery  well  was  drilled  as  an  exploration  for 
sulphur.  At  Sour  Lake,  also  in  the  Gulf  coast  field,  acid  waters 
were  among  the  surface  indications  that  led  to  drilling. 

Sulphur  and  acid  waters,  like  salt  and  salt  water,  are  widely 
distributed  in  the  earth.  It  is  only  in  certain  surroundings  that  they 
are  of  interest  as  indications  that  suggest  of  the  possible  presence 
of  petroleum, 


CHAPTER  III 

OPENINGS  IN  ROCKS1 
SIZES  OF  OPENINGS 

Openings  may  be  classified  with  respect  to  their  size  and  with 
respect  to  their  origin.  With  respect  to  size,  they  may  be  placed 
in  three  groups — supercapillary,  capillary,  and  subcapillary.2 

Supercapillary  openings  are  those  in  which  water  obeys  the 
ordinary  laws  of  hydrostatics.  For  water  at  ordinary  tempera- 
tures, tubes  with  holes  more  than  0.508  millimeter  in  diameter  or 
sheet  openings  more  than  0.254  millimeter  wide  are  super- 
capillary. 

Capillary  openings  are  tubes  with  holes  less  than  0.508  and 
greater  than  0.0002  millimeter  in  diameter,  or  sheet  openings 
between  0.254  and  0.0001  millimeter  wide.  In  these  water  does 
not  obey  the  ordinary  laws  of  hydrostatics  but  is  affected  by 
capillary  attraction.  Water  will  not  circulate  so  freely  in  such 
openings  because  of  the  greater  friction  along  the  walls.  Hot 
water  may  move  through  such  openings  more  readily  than  cold, 
however,  and  under  pressure  either  hot  or  cold  solutions  may  be 
forced  through  capillary  openings. 

Subcapillary  openings  include  tubes  with  holes  less  than  0.0002 
millimeter  in  diameter  and  sheet  openings  less  than  0.0001  milli- 
meter wide.  In  these  the  attraction  of  the  molecules  of  the  solid 
extends  across  the  open  space.  Water  may  enter  such  openings, 
but  it  tends  to  remain  as  if  fixed  to  the  walls,  prohibiting  further 
entrance  of  solutions.  Circulation  of  solutions  at  ordinary  tem- 
peratures through  such  openings  is  therefore  very  slow. 

If  two  rocks  have  equal  amounts  of  pore  space — supercapillary 
in  one  and  subcapillary  in  the  other — ^the  one  with  the  larger 
openings  will  afford  more  favorable  conditions  for  the  movement 
of  fluids.  Muds,  clays,  shales,  and  rock  powders,  which  contain 

irrhis  chapter  is  an  abridgment  of  a  discussion  of  openings  in  rocks  in  an 
earlier  volume  by  the  writer,  "The  Principles  of  Economic  Geology,"  New 
York,  1918. 

DANIEL,  ALFRED:  A  Text-book  of  the  Principles  of  Physics.    P.  315,  1895. 

VAN  HISE,  C.  R. :  A  Treatise  on  Metamorphism.  U.  S.  Geol.  Survey  Mon. 
47,  p.  135,  1904, 

41 


42  GEOLOGY  OF  PETROLEUM 

exceedingly  minute  openings,  are  the  great  natural  barriers  to 
circulation,  although,  under  sufficient  pressure,  fluids  are  forced 

through  them. 

ORIGIN  OF  OPENINGS 

With  respect  to  their  origin,  openings  in  rocks  are  classified  as 
follows : 

Primary  Openings: 

Intergranular  spaces. 
Bedding  planes. 
%  Vesicular  spaces. 
Openings  in  pumice. 
Miarolitic  cavities. 
Submicroscopic  spaces. 

Secondary  Openings: 

Openings  formed  by  solution. 

Shrinkage  cracks  due  to  dehydration,  cooling,  loss  of 

fluids,  etc. 

Openings  due  to  force  of  crystallization. 
Openings  due  to  the  thrust  of  solutions. 
Openings  due  to  the  greater  earth  stresses. 

PRIMARY  OPENINGS 

Intergranular  Spaces  in  Sedimentary  Rocks. — The  pore  spaces 
in  sedimentary  rocks  constitute  a  percentage  of  the  volume  of 
the  rock  ranging  from  less  than  1  up  to  25  or  even  more.  Accord- 
ing to  Buckley,1  the  Dunnville  sandstone  of  Wisconsin  has  a  pore 
space  of  28.28  per  cent.  Many  sandstones  have  20  per  cent  or 
more.  As  shown  by  Slichter,2  the  size  of  the  grains  does  not 
determine  the  amount  of  pore  space:  a  fine-grained  rock  may  be 
as  porous  as  a  coarse  conglomerate.  Fig.  8  shows  a  pile  of  balls 
arranged  in  the  most  compact  manner  possible.  Fig.  9  shows 
the  spaces  between  the  balls  of  Fig.  8.  It  is  obvious  that  if  these 
balls  were  increased  or  decreased  in  size  the  changes  would  affect 
similarly  the  spaces  between  them.  The  amount  of  space  depends 
principally  upon  the  assortment  of  grains  and  the  system  of  pack- 

^UCKLEY,  E.  R  :  Building  and  Ornamental  Stones  of  Wisconsin.  Wiscon> 
sin  Geol.  and  Nat.  Hist.  Survey  Bull  4,  pp.  225,  403,  1898. 

SLIGHTER,  C.  S. :  Theoretical  Investigation  of  the  Motion  of  Groun-! 
Waters.  U.  S.  Geol.  Survey  Nineteenth  Ann.  Rept.,  part  2,  p.  305,  1899. 


OPENINGS  IN  ROCKS 


43 


FIG.  8. — Spheres  packed  in  the  most  compact  manner  possible.  The  face  angles 
are  60°  and  120°.  (After  Stickler.) 


FIG.  9. — Cast  showing  pore  space  in  a  mass  of  spheres  packed  in  the  most 
compact  manner  possible.  (After  Stickier. ) 


44  GEOLOGY  OF  PETROLEUM 

ing.  If  small  grains  fill  in  the  spaces  between  large  grains,  the 
porosity  is  obviously  diminished.  The  fact  that  very  fine  material 
will  not  permit  the  free  movement  of  fluids  is  not  due  to  the  absence 
of  openings  but  to  the  small  size  of  the  openings.  In  rock  with 
subcapillary  openings  fluids  tend  to  remain  fixed  to  the  rock 
particles.  The  pore  spaces  of  the  more  coarsely  granular  rocks, 
such  as  sandstone,  are  more  likely  to  serve  as  reservoirs  for  fluids 
than  those  in  fine-grained  rocks,  such  as  shales.  Clay  particles 
are  small,  and  because  many  are  flat  they  pack  closely.  More- 
over, colloidal  matter  in  clay  and  shale  tends  to  decrease  perme- 
ability. Under  sufficient  pressure,  however,  fluids  will  be  driven 
through  even  clays  and  shales. 

Some  sedimentary  rocks  contain  large  numbers  of  fossil  shells 
that  are  hollow,  some  beds  being  made  up  largely  of  such  shells. 
The  porosity  of  such  a  bed  may  be  very  great. 

Bedding  Planes.  —  Bedding  planes  are  due  to  the  assortment  or 
sizing  of  material  during  transportation  and  deposition.  On 
account  of  the  assortment  of  grains  there  is  also  a  different  arrange- 
ment of  the  pore  spaces  in  the  different  beds.1  Consequently, 
even  in  a  nearly  homogeneous  rock  the  different  beds  commonly 
have  different  degrees  of  permeability.  Fluids  moving  along  the 
beds  may  follow  the  most  permeable  layer,  but  fluids  moving 
across  them  must  traverse  also  the  most  impermeable  layers. 
Fluids  will  therefore  pass  along  beds  more  readily  than  across  them. 

Vesicular  Spaces.  —  Magmas  generally  contain  included  fluids. 
When  the  magmas  are  erupted  and  flow  out  upon  the  surface, 
pressure  is  relieved  and  the  fluids  expand  and  escape  as  gases.  If 
they  expand  when  the  lavas  are  in  a  sticky  or  viscous  condition 
and  near  the  point  of  solidification  the  openings  due  to  expansion 
are  preserved.  The  openings  due  to  expanded  gases  in  lavas, 
unlike  the  pores  in  sandstone,  are  generally  not  connected  and 
therefore  do  not  offer  continuous  passages  to  fluids. 

Openings  in  Pumice.  —  Pumices  are  lavas  that  contain  very  large 
amounts  of  pore  space.  The  openings  are  formed  in  the  same 
manner  as  vesicles  but  are  generally  smaller  and  much  more  numer- 
ous. Siliceous  lavas,  such  as  rhyolites  and  other  acidic  rocks, 
are  more  viscous  than  basic  lavas,  such  as  basalt  or  diabase.  Rock 


F.  H.:  Principles  and  Conditions  of  the  Movements  of  Ground 
Water.   U.  S.  Geol.  Survey  Nineteenth  Ann.  Rept.,  part  2,  p.  135,  1899. 


OPENINGS  IN  ROCKS  45 

froth  is  more  generally  formed  with  siliceous  material,  although 
both  acidic  and  basic  lavas  are  commonly  vesicular.  Open  spaces 
in  a  pumice  are  not  continuous,  and  the  circulation  in  them  is  slow. 
Fragments  of  pumice  placed  in  water  may  float  for  days  before  the 
spaces  are  filled  and  the  water-logged  fragments  sink.  Petroleum 
deposits  in  pumice  are  rare  or  unknown. 

Miarolitic  Cavities. — Some  igneous  rocks  and  some  pegmatites 
contain  small  openings  which  are  believed  to  be  spaces  formerly 
occupied  by  fluids  of  the  rock  magma  that  were  unable  to  escape 
during  the  solidification  of  the  rock.  Such  openings,  called  miaro- 
litic,  are  present  in  rocks  that  solidified  under  pressure  and  are 
unlike  vesicles,  although  both  are  due  to  imprisoned  fluids.  The 
walls  of  miarolitic  cavities  are  usually  rough,  because  they  are  lined 
by  crystals  of  the  rock.  Miarolitic  cavities  are  not  known  to  be 
seats  of  accumulations  of  petroleum. 

Submicroscopic  Spaces. — The  denser  rocks,  which  appear  solid, 
contain  nevertheless  small  amounts  of  pore  space.  A  granite, 
which  under  the  microscope  has  no  visible  openings,  will  absorb 
a  small  amount  of  water  in  the  cold.  Shales  contain  numerous 
openings,  but  these  do  not  permit  the  ready  passage  of  fluids 
because  they  are  largely  subcapillary.  Under  pressure,  however, 
fluids  are  forced  into  or  through  subcapillary  openings. 

SECONDARY  OPENINGS 

Openings  Fonned  by  Solution. — In  soluble  rocks  like  lime- 
stones and  dolomites  large  openings  may  be  formed  by  solution 
and  by  removal  of  rock  matter.  Solution  usually  proceeds  by 
enlarging  smaller  openings,  such  as  joints,  bedding  planes,  or 
fissures.  These  openings  may  become  the  principal  drainage 
channels  of  the  country,  and  the  solution  cavities  along  them  may 
be  developed  on  an  enormous  scale.  As  a  rule  solution  is  more 
active  above  the  water  level,  but  large  cavities  have  been  found 
considerably  below  the  present  water  level.  Where  an  ancient 
drainage  surface  is  buried  by  later  strata  solution  cavities  may  be 
found  at  great  depths. 

Openings  Due  to  Shrinkage. — Shrinkage  may  be  caused  by 
dolomitization,  dehydration,  cooling,  and  other  processes.  If  a 
fairly  pure  limestone  is  changed  to  dolomite  without  addition  of 
carbon  dioxide  a  shrinkage  of  about  12  per  cent  takes  place.  The 


46  GEOLOGY  OF  PETROLEUM 

porosity  of  some  dolomites  is  assumed  to  be  due  to  shrinkage. 
Cracks  due  to  shrinkage  in  drying  are  common.  Cooling  cracks 
are  formed  soon  after  the  solidification  of  igneous  rocks,  before 
they  have  cooled  to  the  temperatures  of  the  surrounding  rocks. 

Openings  Due  to  the  Force  of  Crystallization. — The  force 
which  crystallizing  matter  exerts  on  the  containing  walls  has 
been  assumed  to  be  sufficient  to  push  the  walls  apart.  If  this 
force  so  operates  it  would  be  supposed  that  a  solution,  having  once 
gained  entrance  to  a  fissure,  however  narrow,  could  enlarge  the 
fissure  while  it  was  being  filled.  This  process  does  not  produce 
open  spaces  but  is  assumed  to  widen  those  already  formed.  Becker 
and  Day1  performed  experiments  to  ascertain  the  strength  of  such 
a  force  and  found  it  to  be  of  the  same  order  as  the  crushing  strength 
of  crystals.  They  say:  "It  is  manifest  that  we  here  have  to  deal 
with  a  force  of  great  geological  importance.  If  quartz,  during 
crystallization,  exerts  a  pressure  on  the  sides  of  a  vein  which  is  of 
the  same  order  of  magnitude  which  it  offers  to, crushing,  then  this 
force  is  also  of  the  same  order  of  magnitude  as  the  resistance  of  the 
wall  rocks,  and  it  thus  becomes  possible  that  *  :c  *  veins  have 
actually  been  widened  to  an  important  extent,  perhaps  as  much  as 
100  per  cent  or  even  more,  by  pressure  due  to  this  cause." 

Dunn2  considers  the  force  of  crystallization  as  an  agent  that  has 
operated  in  expanding  the  openings  of  quartz-filled  reefs  of  Ben- 
digo,  Victoria.  The  hypothesis  appears,  however,  to  be  of  limited 
application,  if  not  untenable  for  many  deposits.  Very  commonly 
veins  show  numerous  vugs,  and  it  is  improbable  that  crystals, 
where  they  could  grow  freely  into  open  spaces,  would  thrust  aside 
great  masses  of  rock.  Moreover,  the  crystals  themselves  are 
generally  not  distorted.  They  do  not  show  that  their  own  growth 
was  affected  by  such  enormous  pressures  as  are  demanded  by 
this  hypothesis. 

Harris 3  has  appealed  to  this  force  in  an  hypothesis  which  he  pro- 
posed to  account  for  the  salt  domes  of  the  Gulf  coast  region,  and 
many  investigators  working  in  that  region  have  accepted  his 

DECKER,  G.  F.,  and  DAY,  A.  L.:  The  Linear  Force  of  Growing  Crystals. 
Washington  AcacL  Sci.  Proc.,  vol.  7,  pp.  282-288,  1905. 

2DuNN,  E.  J.:  Report  on  the  Bendigo  Gold  Field,  Victoria.  P.  25,  Dept. 
of  Mines,  1896. 

HARRIS,  G.  D. :  Oil  and  Gas  in  Louisiana,  With  a  Brief  Summary  of  Their 
Occurrence  in  Adjacent  States.  U.  S.  Geol.  Survey  Bull.  429,  p.  8,  1910. 


OPENINGS  IN  ROCKS  47 

hypothesis.  The  puzzling  genesis  of  the  salt  domes,  however, 
should  be  regarded  as  a  problem  that  is  only  in  process  of  solution 
(p.  372). 

Openings  Due  to  Greater  Stresses. — The  openings  that  are  due 
to  the  greater  stresses  attending  the  deformation  of  the  earth  are 
the  seats  of  the  larger  number  of  the  world's  metalliferous  deposits. 
Such  openings,  however,  are  less  significant  in  connection  with  the 
origin  of  the  bitumens.  Many  dikes  of  ozokerite,  gilsonite,  and 
other  bitumens  have  formed  by  the  drying  out  of  petroleum  in 
great  fractures.  Few  metalliferous  veins  filling  openings  in  rocks 
are  longer  or  wider  than  the  great  gilsonite  dikes  of  the  Uinta 
Basin,  Utah.  In  some  regions  that  yield  petroleum  fissures  and 
zones  of  fracturing  have  served  as  passages  between  the  strata  in 
which  the  petroleum  and  gas  originated  and  the  strata  in  which 
they  accumulated.  In  a  few  regions  the  fissures  in  rocks  serve  as 
the  petroleum  and  gas  reservoirs. 


CHAPTER  IV 
ASSOCIATION  OF  PETROLEUM  AND  SALT  WATER 

Salt  water  is  associated  with  petroleum  in  practically  all  the 
large  oil-producing  regions  in  the  world  and  in  nearly  all  prolific 
oil  pools  in  these  regions  (Fig.  10.)  In  the  Appalachian  oil  fields 
salt  water  generally  saturates  the  petroliferous  strata  below  the 
Catskill  formation  and  also  some  of  the  petroliferous  strata  above 
the  Catskill.  The  Catskill  itself  is  not  saturated.  This  series  is  of 
terrestrial  origin.  According  to  Reeves,1  in  places  the  pore  space 
in  the  Catskill  sands  is  filled  with  air.  The  sediments  had  evi- 
dently dried  out  before  they  were  submerged  in  the  sea.  This 
series,  which  embraces  the  Venango  oil  sand  group,  is  very  prolific 


'-•  Salt  Wafer-- 


FIG.  10. — Sketch  showing  a  common  relationship  of  oil,  gas,  salt  water, 
water  somewhat  salty,  and  fresh  water.  The  circulation  of  fresh  ground  water 
sweeps  out  the  brine  near  the  surface  and  dilutes  it  in  depth. 

in  southwestern  Pennsylvania.     In  the  Venango  group  the  oil  is 
found  in  synclines.  (See  p.  212.) 

In  the  Ohio  portion  of  the  Appalachian  field  the  Pennsylvanian 
and  Mississippian  strata  carry  salt  water.  In  the  Clinton  gas  field 
the  Big  lime  (Silurian),  which  lies  a  short  distance  above  the 
"Clinton"  sand,  is  soaked  with  brine.  Near  Bremen,  Fairfield 
County,  a  very  light  oil  is  found  in  the  Clinton  in  a  small  pool  that 
appears  to  be  free  from  water.2  From  this  fact  Bownocker  con- 
cludes that  the  oil  is  in  shallow  basins  rather  than  on  the  slopes  of 
anticlines.  It  seems  probable  that  the  oil  is  perched  in  this  basin 
and  that  gas  rather  than  brine  may  be  found  in  the  Clinton  below . 

BEEVES,  FRANK:  Absence  of  Water  in  Sandstones  of.  the  Appalachian  Oil 
Fields.  Econ.  Geology,  vol.  12,  pp.  254-278,  1917. 

2BowNOCKER,  J.  A.:  Petroleum  in  Ohio  and  Indiana.  Geol.  Soc.  Amer- 
ica Bull.,  vol.  28,  p.  672,  1917. 

48 


ASSOCIATION  OF  PETROLEUM  49 

the  pool.  This  occurrence  of  oil  free  from  water,  according  to 
Bownocker,  is  unusual  in  Ohio. 

In  the  Lima-Indiana  field,  where  oil  and  gas  are  found  in  the 
Trenton  limestone,  salt  water  rises  to  nearly  equal  altitudes. 
In  the  Irvine  field,  eastern  Kentucky,1  salt  water  is  associated  with 
the  oil,  some  wells  yielding  considerable  quantities.  In  the  Wayne 
County  and  McCreary  County  fields,2  in  southern  Kentucky,  oil 
is  found  in  Paleozoic  rocks.  Where  the  oil  lies  in  synclines  the 
rocks  do  not  contain  water.  Salt  water  is  present  in  the  Spurrier 
region,  Tennessee. 

In  Lambton  County,  Ontario,  the  petroliferous  strata  carry  salt 
water.  The  Dundee  (Corniferous)  formation  in  southern  Mich- 
igan contains  brine.3 

In  Illinois  petroleum  is  found  chiefly  in  the  lower  part  of  the 
Pennsylvanian  and  upper  part  of  the  Mississippian  rocks,  in  both 
of  which  it  is  associated  with  much  salt  water.  As  stated  by  Kay4 
in  the  bottom  of  the  Illinois  basin  and  well  up  on  its  sides  the  Potts- 
ville  rocks  are  saturated  with  salt  water. 

In  the  Oklahoma-Kansas  field  salt  water  is  associated  with  the 
oil,  and  in  the  western  part  of  the  field  the  sands  are  saturated  and 
the  oil  and  water  are  under  considerable  pressure.  In  the  Red 
River  field  of  southern  Oklahoma  and  northern  Texas,  and  in  the 
Ranger  field  of  Texas  the  petroliferous  rocks  are  saturated  with 
brine. 

In  the  fields  of  northern  Louisiana  and  eastern  Texas,  where  oil 
is  obtained  from  the  Upper  Cretaceous  beds,  salt  water  is  present 
in  the  producing  members.  The  Woodbine  sand  yields  oil  and  gas 
in  Louisiana  and  at  South  Bosque,  Texas.  At  both  places  it 
carries  brine.  At  Corsicana,  Texas,  where  the  Woodbine  is  bar- 
ren, it  yields  water  that  is  only  slightly  saline.  The  Blossom  sand 
at  Caddo,  Louisiana,  carries  oil  and  salt  water.  The  Nacatoch 
sand  is  saturated  with  brine  in  the  Caddo  field.  The  Taylor  marl 


,  E.  W.  :  The  Irvine  Oil  Field,  Estill  County,  Kentucky.  U.  S.  Geol. 
Survey  Bull.  661,  p.  149,  1918. 

^EMBERTON,  J.  R.  i  A  Resume  of  the  Past  Year's  Development  in  Kentucky 
From  a  Geologic  Standpoint.  Am.  Assoc.  Pet.  Geol.  Bull,  vol.  2,  pp.  38-53, 
1918. 

3SMiTH,  R.  A.:  The  Occurrence  of  Oil  and  Gas  in  Michigan.  Michigan 
Geol.  and  Biol.  Survey  Pub.  14,  Geol.  ser.  11,  p.  27,  1914. 

4KAY,  F.  H.  :  Oil  Fields  of  Illinois.  Geol.  Soc.  America  Bull,  vol.  28,  p.  657, 
1917. 


50  GEOLOGY  OF  PETROLEUM 

carries  salt  water  at  Thrall,  Texas.  Salt  water  and  salt  are 
associated  with  petroleum  in  the  salt-dome  field  of  Texas  and 
Louisiana. 

In  the  West,  also,  salt  water  is  associated  with  petroleum  in 
nearly  every  large  field.  It  is  present  in  all  the  producing  fields  of 
Wyoming  except  in  the  Grass  Creek  anticline  of  the  Big  Horn 
Basin  and  some  neighboring  anticlines,  where  the  oil  is  floated  on 
a  water  that  is  only  slightly  salty  or  feebly  alkaline.  In  this 
region,  as  stated  by  Hewett  and  Lupton,1  there  has  probably  been 
accession  of  surface  water  to  the  beds  from  the  outcrops.  In  the 
Salt  Creek  field  the  oil  is  floated  on  brine.  Recently,  however,  a 
well  sunk  near  a  fault,  on  the  west  border  of  this  field,  yielded  com- 
paratively fresh  water.  In  the  Pecos  Valley,  New  Mexico,  a  heavy 
black  oil  is  associated  with  water  that  rises  copiously  into  artesian 
wells.  The  water  carries  a  considerable  concentration  of  salts  in 
some  wells  but  very  little  salt  in  others. 2  In  California  the  petro- 
Jeum  is  associated  with  brine. 

In  Mexico  great  quantities  of  salt  water  are  encountered  in  the 
petroleunir-bearing  strata.  The  Dos  Bocas  well,  after  spouting  oil 
heavily  for  58  days,  began  to  discharge  hot  salt  water,  yielding 
1,500,000  barrels  a  day. 

In  the  Boryslaw  region,  Galicia,  oil  occurs  in  the  Miocene  salt 
shale  and  Saliferous  clays,  and  in  Rumania  in  the  Saliferous  clays. 
In  Rumania  oil  is  associated  with  salt  water  and  some  with  salt. 
In  the  Berca  and  Becieu  fields3  salt  efflorescences  accompany  oil 
seeps  and  mud  volcanoes  above  the  producing  anticlines. 

In  the  Baku  field,  Russia,  all  the  deep  waters  are  brines.  At 
Holy  Island  salt  water  issues  in  the  oil  fields.  In  Egypt  salt  and 
salt  water  are  closely  associated  with  the  petroliferous  beds.  In 
the  Irrawady  River  field,  Burma,  the  oil  is  floated  on  salt  water. 
Noteworthy  features  of  the  water  of  Yenangyaung,  as  indicated 
by  analyses  reported  by  Pascoe,  are  the  large  amount  of  carbonates 
and  the  absence  or  low  content  of  sulphates. 

HEWETT,  D.  F.,  and  LUPTON,  C.  T.:  Anticlines  in  the  Southern  Part  of 
the  Big  Horn  Basin,  Wyoming.  U.  S.  Geol.  Survey  Bull.  656,  pp.  46,  156, 
1917. 

2FiSHER,  C.  A. :  Geology  and  Underground  Waters  of  the  Roswell  Artesian 
Basin,  New  Mexico.  U.  S.  Geol.  Survey  Water-Supply  Paper  158,  1906. 

3PREiswERK,  H. :  Ueber  den  Geologischen  Bau  der  Region  der  Schlamm- 
vulkane  und  Oelfelder  von  Berca  und  Becieu  bei  Buzen  in  Rumanien.  Zeitschr. 
prakt.  Geologic,  1912,  pp.  86-95. 


ASSOCIATION  OF  PETROLEUM  51 

The  waters  of  the  oil  fields  of  California  were  investigated  by 
Rogers1.  The  water-bearing  sands  are  generally  encountered 
above,  below,  and,  in  many  places,  in  the  oil  measures.  The  water 
in  many  of  the  sands  is  under  high  pressure.  Some  of  the  ground 
waters  are  as  salty  as  ocean  water,  but  others  are  fresh.  This 
difference  is  believed  to  be  the  result  of  difference  in  freedom  of 
circulation,  which  is  controlled  by  the  structure.  Where  the  struc- 
ture prevents  circulation  the  ground  water  is  salty,  but  where  it 
does  not  and  circulation  is  relatively  free,  surface  water  has  entered 
the  beds  and  replaced  much  of  the  strong  chloride  water  originally 
present.  Ground  water  near  the  surface  and  near  the  outcrops  of 
the  beds  is  comparatively  fresh,  but  the  content  of  chloride  gen- 
erally increases  with  depth.  The  deeper  waters  trapped  in  struc- 
tural troughs,  like  the  Midway  syncline,  closely  resemble  ocean 
water  in  most  respects  and  are  believed  to  be  only  slightly  altered 
sea  water.  The  surface  waters  and  shallow  ground  waters  and 
also  the  deeper  ground  waters  outside  the  oil  fields  on  the  west  side 
of  San  Joaquin  Valley  contain  sulphate.  In  the  oil  fields,  however, 
the  content  of  sulphate  decreases  with  depth,  and  ground  waters 
near  and  in  the  oil  measures  are  practically  free  from  sulphate. 
This  decrease  in  sulphate  is  attended  by  a  corresponding  increase 
in  carbonate,  and  in  districts  in  which  chloride  is  not  abundant  the 
waters  near  the  oil  measures  are  nearly  pure  carbonate  waters. 
Where  chloride  is  the  predominating  acid  radical,  even  in  the 
shallower  waters,  carbonate  is  unimportant,  and  the  chief  change 
with  depth  is  the  disappearance  of  the  sulphate.  The  amount  of 
sulphide  in  the  deeper  waters  is  roughly  proportional  to  the 
amount  of  sulphate  in  the  waters  directly  above  them,  or  nearer  the 
surface.  Calcium  and  magnesium  predominate  in  many  of  the 
surface  waters,  but  sodium  and  potassium  greatly  predominate  in 
the  deeper  waters.  Most  of  the  waters  associated  with  the  oil  are 
therefore  variously  proportioned  mixtures  of  solutions  of  alkaline 
carbonates  and  chlorides,  the  proportion  of  carbonate  depending 
chiefly  on  the  extent  to  which  meteoric  water  is  able  to  enter  at  the 
outcrop. 

When  gases  under  high  pressure  are  released  they  expand  and 
the  salt  solution,  carried  as  spray,  becomes  cooler  and  deposits 
salts  by  evaporation  of  water  in  their  reservoir  rocks  and  in  casings 

ROGERS,  G.  S. :  Chemical  Relations  of  the  Oil-field  Waters  in  San  Joaquin 
Valley,  California.  U.  S.  Geol.  Survey  Butt.  653,  p.  113,  1917. 


52  GEOLOGY  OF  PETROLEUM 

of  wells.  Mills  and  Wells1  state  that  waters  associated  with  petro- 
leum undergo  deep-seated  concentration,  brought  about  by  their 
evaporation  into  moving  and  expanding  gas.  During  this  con- 
centration there  is  a  definite  order  of  change  in  the  relative  pro- 
portions of  the  dissolved  constituents  in  the  waters.  Carbon 
dioxide  and  other  gases  are  lost  from  solution.  Calcium,  magne- 
sium, and  iron  separate  from  solution  as  carbonates,  and  under 
favorable  conditions  sodium  and  minor  proportions  of  calcium  and 
magnesium  separate  as  chlorides — a  process  similar  to  the  salting 
up  of  gas  wells.  A  further  separation  of  the  dissolved  constituents, 
more  particularly  of  calcium,  magnesium,  iron,  sodium,  barium, 
strontium,  carbonate,  and  silica,  is  brought  about  when  waters 
from  different  beds  and  having  different  properties  of  reaction 
become  mixed.  The  ratio  of  calcium  to  chlorine  in  the  waters 
increases  and  the  ratio  of  sodium  to  chlorine  decreases  with  the 
concentration.  Mills  and  Wells  state  that  concentration  by 
natural  processes  is  brought  about  much  as  it  is  in  wells,  the  gas 
pressure  being  gradually  relieved  by  leakage  of  reservoirs  where 
gas  escapes  in  seeps  at  the  surface,  or  into  other  strata  containing 
gas  at  a  lower  pressure. 

aMiLLS,  R.  V.  A.,  and  WELLS,  R.  C.:  The  Evaporation  and  Concentration 
of  Waters  Associated  with  Petroleum  and  Natural  Gas.  U.  S.  Geol.  Survey 
Bull  693,  pp.  1-103,  1919. 


CHAPTER  V 

RESERVOIR  ROCKS  AND  COVERING  STRATA 
RESERVOIR  ROCKS 

General  Character. — The  reservoirs  that  contain  oil  and  gas  are 
the  pore  spaces  in  sands,  sandstones,  and  sandy  marls  and  the 
pores,  solution  cavities,  and  fissures  in  limestones,  dolomites,  and 
other  sedimentary  rocks.  Oil  is  found  in  fissures  in  indurated 
shale  and  in  fissures  in  igneous  rock,  but  such  occurrences  are  com- 
paratively rare. 

In  Pennsylvania  and  West  Virginia,  altogether,  there  are  thirty- 
seven  reservoir  strata,1  of  which  thirty-five  are  sands  and  sand- 
stones, one  a  conglomerate,  and  one  a  limestone.  The  limestone 
is  the  Greenbrier,  of  Mississippian  age. 

Of  the  eight  principal  reservoir  strata  in  Ohio2  seven  are  sands 
and  one,  the  Trenton,  is  limestone. 

In  Indiana2  the  Huron  sandstone,  the  Jeffersonville  or  "Cornif- 
erous"  limestone,  and  the  Trenton  limestone  are  the  chief  reservoir 
strata. 

In  Kentucky  the  principal  reservoir  stratum  is  the  Jeffersonville 
or  "Corniferous"  limestone,  although  oil  or  gas  or  both  are  found 
also  in  many  sands,  and  a  small  production  is  derived  from  lime- 
stones below  the  Devonian. 

In  the  Spurrier  and  Riverton  districts,  Tennessee,  the  oil  is 
derived  from  Ordovician  limestone.  In  the  Glenmary  district  it 
is  obtained  probably  from  an  oolitic  limestone. 3 

In  the  Fayette  gas  field  of  Alabama4  gas  is  derived  from  sands. 

In  Michigan15  oil  is  derived  from  the  Dundee  limestone. 

DULLER,  M.  L.:  Appalachian  Oil  Field.  Geol.  Soc.  America  Bull.,  vol.  28. 
p.  633,  1917. 

2BowNocKER,  J.  A. :  Petroleum  in  Ohio  and  Indiana.  Geol.  Soc.  America 
Bull.,  vol.  28,  pp.  667-676,  1917. 

'GLENN,  L.  C.:  Recent  Oil  Development  of  Glenmary,  Scott  County, 
Tennessee:  Resources  of  Tennessee.  Vol.  7,  p.  40,  1917. 

4MuNN,  M.  J.:  The  Fayette  Gas  Field,  Alabama.  U.  S.  Geol.  Bull.  471, 
p.  38,  1912. 

5SMiTH,  R.  A. :  The  Occurrence  of  Oil  and  Gas  in  Michigan.  Michigan  Geol. 
and  Biol.  Survey  Pub.  14,  Geol.  ser.  11,  pp.  1-281,  1914. 

53 


54  GEOLOGY  OF  PETROLEUM 

In  Illinois1  in  the  principal  producing  district  there  are  seven 
reservoir  strata.  All  of  them  are  sands  or  sandstones  except  the 
so-called  McClosky  sand,  which  is  an  oolitic  limestone,  and  the 
Trenton  dolomite. 

In  the  Oklahoma-Kansas  field  the  chief  reservoir  strata  are 
sands.  In  Oklahoma,  as  shown  by  Aurin,2  there  are  more  than 
40  producing  strata,  of  which  all  but  two  are  sands.  The  Oologah, 
or  Big  lime  and  the  Oswego  or  Fort  Scott  limestone,  of  the  Penn- 
sylvanian,  at  places  form  reservoirs.  Gardner3  states  that  90  per 
cent  of  the  Oklahoma  production  has  been  derived  from  a  single 
sand,  the  Bartlesville. 

In  the  Arkansas  gas  field  near  Fort  Smith,4  and  in  the  oil  field 
south  of  Kansas  City,  Missouri,5  the  reservoir  strata  are  sand- 
stones. 

In  the  Red  River  district  of  southern  Oklahoma  and  northern 
Texas  the  reservoir  rocks  are  sandstones.  In  the  Ranger  and 
neighboring  districts  the  principal  reservoir  strata  are  sandstone. 
In  the  Ranger  and  Caddo  fields  one  reservoir  horizon  is  at  a  con- 
tact between  limestone  and  shale.  In  the  Balcones  fault  region  of 
Texas  and  in  the  northern  Louisiana  fields6  the  chief  reservoir 
strata  are  sands,  although  in  some  districts  the  Austin  (Annona) 
chalk  carries  gas  and  a  heavy  oil,  and  at  Thrall  oil  is  found  in  a 
tuff  included  in  the  Taylor  marl.7  In  the  Gulf  coast  region  of 
Texas  and  Louisiana  oil  and  gas  are  found  in  porous  fractured  lime- 
stone and  in  sands. 

In  the  principal  oil  fields  of  Wyoming  oil  and  gas  are  found  in 
sands.  On  the  Shoshone  anticline,  however,  oil  is  derived  from 

JKAY,  F.  H.:  Oil  Fields  of  Illinois.  Geol.  Soc.  America  Bull,  vol.  28,  p.  657, 
1917. 

2AuRiN,  F.:  Correlation  of  the  Oil  Sands  of  Oklahoma.  Oklahoma  Geol. 
Survey  Circ.  7,  pp.  1-16,  chart,  1917. 

'GARDNER,  J.  A.:  Mid-Continent  Geology.  Oil  and  Gas  Jour.  Suppl, 
May,  p.  7.  1919, 

4SMITH,  C.  D. :  Structure  of  the  Fort  Smith-Poteau  Gas  Field,  Arkansas  and 
Oklahoma.  U.  S.  Geol.  Survey  Bull.  541,  p.  23,  1914. 

6WiLSON,  M.  E. :  Oil  and  Gas  Possibilities  in  the  Belton  Area,  Missouri. 
Missouri  Bur.  Geology  and  Mines,  1918. 

•MATSON,  G.  C.,  and  HOPKINS,  O.  B.:  The  Corsicana  Oil  and  Gas  Field, 
Texas.  U.  S.  Geol.  Survey  Bull  661,  p.  217,  1918. 

7UDDEN,  J.  A.,  and  BYBEE,  H.  P.:  The  Thrall  Oil  Field.  Univ.  of  Texas 
Bull  66,  p.  39,  1916. 


RESERVOIR  ROCKS  AND  COVERING  STRATA   55 

limestones.     A  small  part  of  the  oil  produced  at  Salt  Creek1 
comes  from  fractures  in  shale. 

In  the  Florence  district,  Colorado,2  oil  is  found  in  fissures  in 
shales.  In  the  fields  of  western  Colorado  and  in  Utah  the  oil  and 
gas  are  in  sandy  strata. 

In  California  fields3  the  reservoirs  are  sands  and  conglomerates.  \ 

In  Middlesex  counties  the  principal  producing  area  of  Lambton 
and  the  Ontario  field,  the  oil  and  gas  are  in  Devonian  limestone. 4 
In  Dover  West,  Kent  County,  some  oil  has  been  derived  from  the 
Trenton  limestone,  and  near  Niagara  Falls  gas  is  derived  from  the 
Clinton  sand.  In  the  foothill  region  of  the  Canadian  Rockies  gas 
is  derived  from  sand. 

In  the  Tampico  region  of  Mexico  the  principal  reservoir  rock  is 
limestone,  although  some  oil  is  derived  from  sands  above  it.  In 
Trinidad  oil  is  derived  from  sands.  In  the  coastal  fields  of  Peru 
and  Ecuador  the  oil  is  in  sandstone.  In  the  Comodoro  Rivadavia 
field,  Argentina,  the  reservoir  is  a  coarse  pebbly  sandstone. 

In  Derbyshire,  England,  oil  is  found  in  limestone.  In  Alsace  the 
oil  is  almost  exclusively  confined  to  sandstones  that  are  included 
in  marl  beds. 5  In  the  Boryslaw  field,  Galicia,  according  to  Zuber, e 
the  oil  and  gas  are  in  flaggy  sandstone  in  the  Saliferous  formation, 
and  in  conglomerates  and  sandstones  in  the  Dobrotow  formation, 
which  is  the  richest  in  oil.  In  the  Schodnica  field  the  Eocene  oil 
is  in  thick  sandstone  lenses  and  the  Cretaceous  oils  are  in  sandstone 
lenses  covered  by  shales  or  saline  clays.  In  Rumanian  fields7  the 
oil  reservoirs  are  sands,  sandstones,  conglomerates,  and  probably 

WEGEMANN,  C.  H. :  The  Salt  Creek  Oil  Field,  Wyoming.  U.  S.  Geol. 
Survey  Bull.  670,  p.  36,  1917. 

2WASHBURNE,  C.  W.  i  The  Florence  Oil  Field,  Colorado.  U.  S.  Geol.  Sur- 
vey Bull.  381,  p.  522,  1910. 

'ARNOLD,  RALPH,  and  GARFIAS,  V.  R. :  Geology  and  Technology  of  the 
California  Oil  Fields.  Am.  Inst.  Min.  Eng.  Bull.  87,  p.  405,  1914. 

4WiLLiAMS,  M.  Y.:  Oil  Fields  of  Southwestern  Ontario.  Canada  Dept. 
Mines  Summary  Rept.,  1918,  part  E,  pp.  30-42,  1919. 

6VoN  WERVEKE,  L.:  Vorkommen,  Gewinnen  und  Entstehung  des  Erdols 
in  Unter-Elsass.  Zeitschr.  prakt.  Geologic,  1895,  pp.  97-114. 

6ZuBER,  RUDOLPH:  Die  geologischen  Verhaltnisse  von  Boryslav  in  Ost- 
galizien:  Zeitschr.  prakt.  Geologic,  1904,  pp.  41-48. 

7PREiswERK,  H.:  Ueber  den  Geologischen  Bau  der  Region  der  Schlamm- 
vulcane  und  Oelfelden  von  Berca  und  Becieu  in  Rumanien.  Zeitschr.  prakt. 
Geologic,  1912,  pp.  86-95. 


56  GEOLOGY  OF  PETROLEUM 

volcanic  tuffs.  The  reservoirs  of  the  Baku  field,1  Russia,  are  sands 
of  unusual  thickness.  In  the  Grozny  field1  they  are  sands  and 
sandstones.  In  the  Maikop  field2  the  oil  is  found  in  loose  sands. 
At  Holy  Island  the  oil  is  in  sand. 

The  reservoir  rocks  of  the  Irrawady  River  fields3  in  Burma  are 
sands.  In  Japan  the  reservoirs  are  sandstones  and  volcanic  tuffs. 

It  is  noteworthy  that  the  reservoir  rocks  in  most  oil  fields  are 
sands  and  sandstones.  Among  the  exceptions  are  the  Trenton 
limestone  in  Ohio,  Indiana,  and  Ontario;  the  Devonian  limestone 
in  Ontario,  Michigan,  Indiana,  and  Kentucky;  the  Greenbrier 
limestone  in  Pennsylvania  and  West  Virginia;  the  McClosky 
"sand"  in  Illinois;  the  Oologah  and  Oswego  limestones  in  Okla- 
homa; the  Annona  chalk  of  Louisiana  and  Texas;  the  limestone 
cap  rock  above  the  salt  plugs  in  the  Gulf  coast  region ;  the  Embar 
limestone  of  Wyoming  fields;  the  Tamasopa  limestone  of  Mexican 
fields;  the  Mountain  limestone  in  England;  and  the  oil-bearing 
limestone  of  the  Suez  field,  Egypt. 

The  sandstones  differ  greatly  as  to  size  of  grain.  In  several 
fields  oil  or  gas  or  both  are  found  in  conglomerates — for  example, 
the  Sharon  conglomerate  (Potts ville)  of  the  Pennsylvania- West 
Virginia  region.  The  Vaqueros  formation  of  the  Coalinga  district 
and  the  McKittrick  formation  of  the  McKittrick  district,  Cali- 
fornia, yield  oil  in  part  from  conglomerates.  The  reservoir  of 
the  Comodoro  Rivadavia  district,  Argentina,  is  a  coarse  pebbly 
sand.  In  Rumania  and  Galicia  some  of  the  reservoirs  are  con- 
glomerates. In  the  Galician  fields  the  Dobrotow  formation,  which 
is  very  rich  in  oil,  consists  in  part  of  conglomerates. 

At  many  places  oil  is  found  in  or  near  igneous  rocks,  but  under 
conditions  which  indicate  that  it  migrated  from  sedimentary  strata 
near  by.  In  three  fields  the  productive  reservoirs  are  igneous 
bodies,  but  in  each  of  these  fields  associated  sediments  cover  the 
igneous  bodies  and  in  each  the  igneous  bodies  are,  in  part  at  least, 
tuffs,  breccias,  or  volcanic  ash  and  sand. 

Many  occurrences  of  bitumen  in  porous  igneous  rocks  are  known. 

^DIASSEVICH,  A.:  Oil  Fields  of  Russia.  Am.  Inst.  Min.  Eng.  Trans.,  vol. 
48,  p.  613,  1914. 

FRENCH,  R.  H. :  The  Relationship  of  Structure  and  Petrology  to  the 
Occurrence  of  Petroleum.  (Discussion  of  a  paper  by  A.  B.  THOMPSON.) 
Am.  Inst.  Min.  and  Met.  Trans.,  vol.  20,  p.  247,  1911. 

SPASCOE,  E.  H. :  The  Oil  Fields  of  Burma.  India  Geol.  Survey  Mem.,  vol. 
40,  part  1,  pp.  55-100,  1912. 


RESERVOIR  ROCKS  AND  COVERING  STRATA      57 

One  at  Tar  Point,  Gaspe,  Quebec,  is  noted  by  Logan.1  Clapp2 
mentions  a  vesicular  basalt  .from  Colorado  in  which  the  oil  was 
shown  by  David  T.  Day  to  be  sealed  by  calcite.  Washburne3 
describes  a  porous  basalt  containing  oil  from  the  Johnson  ranch, 
western  Lane  County,  Oregon.  These  examples  could  be  multi- 
plied. It  is  noteworthy  that  none  of  them  give  evidence  of  petro- 
leum originating  in  the  igneous  body  and  that  none  of  them  are  of 
much  commercial  importance. 

In  Cuba,  at  many  places,  small  amounts  of  petroleum  have  been 
obtained  from  fractured  serpentine.  DeGolyer4  states  that  the 
oil  probably  originated  in  Jurassic  or  other  sedimentary  rocks,  and 
then  seeped  into  the  serpentine  from  them. 

The  Thrall  field,  Williamson  County,  Texas,  contains  wells  that 
were  gushers.  The  petroleum  reservoir5  is  a  vesicular,  soft  green 
basic  igneous  rock,  in  the  Taylor  marl.  It  lies  at  a  depth  of  about 
850  feet.  The  top  of  the  igneous  body  is  arched,  so  that  it  has  a 
closure  of  at  least  125  feet.  (See  p.  343.)  The  rock  is  brecciated, 
and  Larsen,  who  examined  specimens  microscopically,  states  that 
some  of  them  appear  to  be  tuff.  The  oil  is  probably  derived  from 
the  Taylor  marl.  It  is  red  in  color  and,  like  that  derived  from  the 
Taylor  marl  in  the  Corsicana  field,  Texas,  has  a  paraffin  base.  It 
is  heavier,  however,  than  the  Corsicana  oil. 

In  the  Furbero  district,  Mexico,  6  igneous  rocks  including  basalt, 
dolerite,  basalt-gabbro,  volcanic  ash  and  sands,  are  covered  by  the 
Mendez  shale  and  possibly  by  other  strata  which  are  indurated 
near  the  igneous  mass.  The  sedimentary  rocks  above  form  an 
anticline.  Petroleum  has  accumulated  in  openings  in  the  igneous 
rocks  and  in  the  Mendez  shale.  DeGolyer  states  that  the  petro- 
leum probably  originated  in  the  Tamasopa  (Cretaceous)  beds. 


,  SIR  WILLIAM:  Geology  of  Canada.     Pp.  405-789,  1863. 

2CLAPP,  F.  G.  :  Revision  of  the  Structural  Classification  of  Petroleum  and 
Natural  Gas  Fields.  Geol.  Soc.  America  Bull,  vol.  28,  p.  592,  1917. 

'WASHBURNE,  C.  W.:  Geology  and  Oil  Prospects  in  Northeastern  Oregon. 
U.  S.  Geol.  Survey  Bull.  590,  p.  100,  1914. 

4DEGoLYER,  E.:  The  Geology  of  Cuban  Petroleum  Deposits.  Assoc.  Am. 
Pet.  Geol.  Butt.  2,  pp.  133-167,  1917. 

5UDDEN,  J.  A.,  and  BYBEE,  H.  P.  :  The  Thrall  Oil  Field.  Texas  Univ.  Bull. 
66,  1916. 

6DEGoLYER,  E.:  The  Furbero  Oil  Field,  Mexico.  Am.  Inst.  Min.  Eng. 
Bull.  105,  pp.  1899-1911,  1915. 


58  GEOLOGY  OF  PETROLEUM 

At  Copper  Mountain,  in  the  Wind  River  Basin,  Wyoming,1  pre- 
Cambrian  granite  forms  the  base  of  a  dome.  Paleozoic  and  later 
strata  dip  away  from  the  granite  on  three  sides  of  the  dome.  On 
the  fourth  side  are  Tertiary  strata,  nearly  flat-lying.  The  granite 
is  fractured  and  faulted,  and  in  it,  in  shafts  and  tunnels,  a  heavy 
asphaltic  oil  and  asphaltum  are  encountered.  The  oil,  according 
to  Trumbull,  was  once  accumulated  in  the  Embar  (Carboniferous) 
beds,  which  elsewhere  contain  a  heavy  oil  and  which,  with  a  thick 
series  of  Paleozoic  and  Cretaceous  rocks,  have  been  eroded  from 
the  dome.  The  oil  may  have  migrated  laterally  as  the  strata  were 
tilted,  or  even  laterally  and  upward  into  the  lower  rocks,  which 
had  been  raised  to  great  altitudes  near  the  center  of  the  dome. 

Petroleum  is  found  in  small  amounts  in  metamorphosed  rocks. 
The  occurrence  at  Furbero,  Mexico,  has  been  mentioned.  A  little 
petroleum  is  found  also  in  a  gneiss  in  the  Santa  Clara  district, 
California.2  In  the  Controller  Bay  region,  Alaska,3  oil  seeps  from 
schists  were  noted,  and  in  the  Copper  Mountain  region,  Wyom- 
ing,4 bitumen  is  found  in  a  hornblendic  rock  and  also  in  the  granite. 
None  of  these  accumulations  are  important  sources. 

Mineral  Composition  of  Reservoir  Rocks. — The  sands  that  form 
the  reservoirs  of  sandy  strata  range  from  fine  sands  to  the  pebbles 
of  conglomerate.  Few  data  are  available  regarding  the  mineral 
character  of  sands  as  shown  by  microscopic  study.  Most  petro- 
liferous sands  consist  mainly  of  quartz,  but  in  some,  feldspar, 
mica,  and  chlorite  are  present.  Pyrite  is  often  abundant.  Some 
petroliferous  sands  contain  fragments  of  heavy  residual  minerals 
such  as  magnetite,  garnet,  ilmenite,  amphibole,  and  monozite. 
Recently  the  method  of  identifying  sands  by  microscopic  study  of 
the  minerals  present  has  been  used  by  operating  companies.  Such 
study  is  expected  to  add  much  to  the  data  available  concerning 
the  mineral  character  of  sands. 

Many  minerals,  on  altering,  yield  clay.  The  fine  particles  of 
kaolin  and  the  colloidal  matter  that  is  present  in  many  clays  tend 
to  seal  openings  between  the  original  mineral  particles.  Many  of 

TRUMBULL,  L.  W.:  Petroleum  in  Granite.  Wyoming  State  Geologist's 
Office  Bull.  1,  Sci.  ser.,  pp.  1-16,  1916. 

2ELDRiDGE,  G.  H. :  The  Santa  Clara  Valley  Oil  District,  Southern  Califor- 
nia. U.  S.  Geol.  Survey  Bull.  309,  p.  5,  1907. 

SMARTIN,  G.  C.:  Geology  and  Mineral  Resources  of  the  Controller  Bay 
Region,  Alaska.  U.  S.  Geol.  Survey  Bull.  335,  p.  42,  1908. 

TRUMBULL,  L.  W.:  op.  tit.,  p.  9. 


RESERVOIR  ROCKS  AND  COVERING  STRATA      59 

the  ferromagnesian  minerals  form  clay  readily  on  weathering. 
These  are  more  abundant,  in  general,  in  basic  rocks  than  in  acidic 
rocks  like  granites.  Sands  derived  from  basic  rocks  are  generally 
less  porous  than  sands  derived  from  acidic  rocks.  Woodruff1 
states  that  certain  sands  of  Cuba  are  derived  largely  from  gabbro 
fragments  and  that  they  have  altered  partly  to  clay,  which  fills  the 
pores  and  limits  their  capacity.  It  is  noteworthy,  however,  that 
fragments  of  limburgite,  a  rather  basic  rock,  are  found  in  the  Thrall 
field,  Texas,2  and  that  basic  igneous  rocks,  in  part  tuffs  and  vol- 
canic sands,  constitute  part  of  the  reservoir  at  Furbero,  Mexico.3 
The  porous  limestones  that  form  reservoirs  include  dolomites 
and  also  limestones  that  are  not  high  in  magnesium.  The  Trenton 
limestone  of  the  Lima-Indiana  oil  field  is  in  the  main  a  dolomite, 
and  Orton  maintained  that  its  porosity  and  ability  to  hold  oil  are 
due  to  dolomitization.  He  showed  by  analyses  that  the  dolomi- 
tized  portion  of  the  formation  is  productive  and  that  where  it  is 
barren  it  is  low  in  magnesia.4  Phinney,5  who  investigated  the 
Indiana  field  after  Orton's  conclusions  had  been  published,  states 
that  the  cavities  of  the  Trenton  are  due  "to  loss  of  substance  and 
not  to  substitution."  He  believed  that  the  formation  is  commonly 
hard  and  uniform  in  texture  and  compact  between  the  irregular 
ramifying  cavities  and  pores  interspersed  through  it.  The  Green- 
brier  limestone,  in  which  some  of  the  oil  of  the  Appalachian  region 
is  found,  is  at  many  places  non-magnesian.  The  Devonian  lime- 
stone, of  the  oil-bearing  region  of  Ontario,  is  somewhat  dolomitic, 
and  the  Devonian  of  eastern  Kentucky  is  dolomitic  in  the  Irvine 
field,  where  it  constitutes  the  reservoir  rock.  The  Tamasopa  lime- 
stone of  the  Mexican  fields  is  said  to  be,  in  ^  part  at  least,  of  low 
magnesia  content. 

Capacities  of  Reservoir  Rocks. — The  amount  of  petroleum  and 

WOODRUFF,  E.  G.:  Petroliferous  Provinces.  Am.  Inst.  Min.  Eng.  Bull. 
150,  p.  909,  1919. 

2UDDEN,  J.  A.,  and  BYBEE,  H.  P.:  The  Thrall  Oil  Field.  Texas  Univ. 
Bull.  66,  p.  39,  1916. 

3DEGoLYER,  E.:  The  Furbero  Oil  Field,  Mexico.  Am.  Inst.  Min.  Eng. 
Bidl.  105,  pp.  1899-1911,  1915. 

4ORTON,  E. :  The  Trenton  Limestone  as  a  Source  of  Petroleum  and  Natural 
Gas  in  Ohio  and  Indiana.  U.  S.  Geol.  Survey  Eighth  Ann.  Rept.,  part  2, 
p.  583,  1889. 

PHINNEY,  A.  J.:  Natural-gas  Field  of  Indiana.  U.  S.  Geol.  Survey  Elev- 
enth Ann.  Rept.,  part  1,  p.  617,  1891. 


60  GEOLOGY  OF  PETROLEUM 

natural  gas  a  reservoir  will  hold  depends  upon  its  size  and  its 
porosity.  The  porosity  of  a  fractured  rock  varies  greatly  because 
of  differences  in  size  and  irregular  spacing  of  fractures.  Porous 
sands,  on  the  other  hand,  are  comparatively  regular,  although 
many  of  them  show  considerable  differences  also.  The  most  porous 
sands  are  those  that  are  made  of  comparatively  uniform  grains 
and  free  from  clay.  Cementation  by  silica,  lime  carbonate,  iron 
oxide,  or  other  substance  will  decrease  porosity.  An  experienced 
driller  can  generally  estimate  the  porosity  of  a  sand  by  its  "feel." 
If  it  is  loose  and  free  from  cement  and  clay  particles,  its  porosity 
is  likely  to  be  high.  Other  tests  include  touching  it  with  the  tongue 
or  blowing  through  it  to  ascertain  porosity.  Chemical  tests  will 
reveal  any  trace  of  oil  (p.  28).  The  amount  of  lime  carbonate  is 
easily  estimated  by  treatment  with  acid. 

Outcrops  of  a  loose-textured,  porous  sandstone  will  show  rounded 
forms  of  sugary  texture.  A  good  example  is  the  St.  Peter  sand- 
stone found  at  Minneapolis  and  at  many  other  places  in  the  Miss- 
issippi Valley.  Under  proper  conditions  this  sand  would  afford  a 
good  reservoir  for  oil  accumulation.  Unfortunately,  the  condi- 
tions other  than  porosity  are  unfavorable.  If  a  sand  is  cemented 
by  silica  its  outcrop  shows  the  customary  jagged  forms  of  quartz- 
ite.  Surfaces  here  and  there  may  be  worn  smooth  and  polished 
by  wind  erosion. 

The  porosity  of  a  sand  does  not  depend  upon  size  of  grain ;  a  fine 
sand  may  have  pore  space  less  than,  equal  to,  or  greater  than  a 
coarse  one.  Uniformity  of  grains,  shape  of  grains,  and  arrange- 
ment or  system  of  packing  affect  porosity.  If  spheres  of  uniform 
size  are  packed  in  tfre  closest  possible  manner  (see  Figs.  8  and  9) 
the  pore  space  between  them  is  25.95  percent  by  volume.1  If  the 
spheres  are  of  different  sizes  the  pore  space  is  less,  because  the 
small  particles  fill  the  spaces  between  the  large  ones.  If  the  par- 
ticles are  of  irregular  or  angular  shape  the  porosity  may  be  greater 
or  less  than  that  of  a  system  of  uniform  spheres,  «but  if  the  material 
is  highly  angular,  with  no  flat  particles,  the  porosity  is  likely  to  be 
greater.  Fig.  11  shows  porous  sands. 

SLIGHTER,  C.  S.:  Theoretical  Investigation  of  the  Motion  of  Ground 
Water.  U.  S.  Geol.  Survey  Nineteenth  Ann.  Rept.,  part  2,  p.  310,  1899. 

KING,  F.  H. :  Conditions  and  Movements  of  Underground  Water.  Idem, 
pp.  209-215. 

LEWIS,  J.  O. :  Methods  for  Increasing  the  Recovery  From  Oil  Sands.  U.  S. 
Bur.  Mines  Bull  148,  pp.  16-20,  1917. 


RESERVOIR  ROCKS  AND  COVERING  STRATA      61 

Buckley1  states  that  the  Dunville  sandstone  of  Wisconsin  has  a 
pore  space  of  28.28  per  cent.  A  specimen  of  the  Wall  Creek  sand, 
which  is  the  principal  petroleum-bearing  stratum  in  the  Salt  Creek 
field,  Wyoming,  collected  by  Wegemann  in  the  Powder  River  field, 
just  west  of  Salt  Creek,  under  tests  made  by  C.  E.  Van  Orstrand, 
showed  a  porosity  of  25.8  per  cent.2  Another  specimen,  somewhat 


(A)  Hoing  sand,  Colmar  field,  Illinois. 


(B)  Producing  sand  of  the  Gushing  field. 


(C)  Grains  of  sand  from  sandstone  shown  in  B,  magnified 

FIG.  11. — Photographs  of  oil  sand.  (From  A.  W.  Lauer,  Econ.  Geology.) 

shaly,  taken  near  the  base  of  the  formation,  has  a  porosity  of  20.4 
per  cent,  and  a  thin  layer  of  calcareous  sandstone  showed  only  7.6 

1BucKLEY,  E.  R. :  Building  and  Ornamental  Stones  of  Wisconsin.  Wiscon- 
sin Geol.  and  Nat.  Hist.  Survey  Bull.  4,  pp.  225,  403,  1898. 

2WEGEMANN,  C.  H. :  The  Salt  Creek  Oil  Field,  Wyoming.  U.  S.  Geol. 
Survey  Bull.  670,  p.  27. 


62  GEOLOGY  OF  PETROLEUM 

per  cent.  The  average  porosity  of  the  Wall  Creek  sand  as  indi- 
cated from  the  three  determinations  is  17.9  per  cent.  The  effective 
porosity,  however,  is  less  than  that,  for,  as  noted  by  Wegemann, 
some  of  the  intergranular  spaces  are  sealed  and  cut  off  from  other 
spaces  by  impervious  material,  so  that  oil  can  not  enter  them. 
The  Shannon  sand  of  Salt  Creek  has  a  porosity  of  26.7  per  cent. 

Van  Orstrand  made  tests  of  the  porosity  of  the  Nacatoch  sand 
member  of  the  Navarro  formation,  which  carries  the  great  gas 
deposits  of  the  Mexia-Groesbeck  field,  Texas.  l  The  results  ranged 
from  16.6  to  34.2  per  cent,  and  the  average  was  25.5  per  cent. 
The  sand  in  this  field  is  uniformly  porous,  according  to  Matson. 
The  pressure,  which  was  originally  276  pounds  to  the  square  inch, 
was  probably  enough  to  force  the  gas  into  minute  pores.  The  oil 
and  gas  bearing  sandstone  of  Petrolia,  Texas,  tested  by  Van 
Orstrand,2  showed  a  porosity  ranging  from  18.5  to  27  per  cent. 

Fragments  of  the  third  sand  at  Oil  City,  Pennsylvania,  were 
tested  by  Carll,3  who  estimated  them  to  be  capable  of  absorbing 
7  to  10  per  cent  of  their  bulk  without  pressure  and  probably  12.5 
per  cent  under  pressure.  Gardner*  estimated  the  porosity  of  the 
Bartlesville  sand  of  Oklahoma  to  be  20  per  cent.  The  porosity  of 
some  of  the  sands  of  Baku,  Russia,  according  to  Thompson,5  is 
25  per  cent  or  more. 

Sandstones  such  as  are  used  for  building  are  not  much  less  porous 
than  some  oil  sandstones.  Buckley  found  the  average  porosity  of 
32  Wisconsin  sandstones6  to  be  15.89  per  cent  and  of  six  Missouri 
sandstones7  to  be  17.74  per  cent.  The  average  of  six  building 
stones  of  Ohio,  according  to  Bownocker,  8  is  16.63  per  cent.  Three 


,  G.  C.:  Gas  Prospects  South  and  Southeast  of  Dallas,  Texas. 
U.  S.  Geol.  Survey  Bull.  629,  p.  87,  1916. 

2SnAW,  E.  W.:  Gas  in  the  Area  North  and  West  of  Fort  Worth,  Texas. 
U.  S.  Geol.  Survey  Bull.  629,  p.  36,  1916. 

3CARLL,  J.  F.  :  The  Geology  of  the  Oil  Regions  of  Warren,  Venango,  Clarion, 
and  Billings  Counties,  Pennsylvania.  Second  Geol.  Survey,  vol.  3,  p.  251,  1880. 

4GARDNER,  J.  H.:  Mid-Continent  Geology.  Oil  and  Gas  Jour.  Suppl.,  May, 
1919,  p.  7. 

THOMPSON,  A.  B.:  The  Oil  Fields  of  Russia.     P.  45,  London,  1904. 

BUCKLEY,  E.  R.  :  Building  and  Ornamental  Stones  of  Wisconsin.  Wisconsin 
Geol.  and  Nat.  Hist.  Survey  Bull  4,  Econ.  ser.  2,  p.  402,  1898. 

BUCKLEY,  E.  R.:  The  Quarry  Industry  of  Missouri.  Missouri  Geology 
and  Mines,  vol.  2,  2d  ser.,  p.  317,  1904. 

8BowNOCKER,  J.  A.:  Building  Stones  of  Ohio.  Ohio  Geol.  Survey  Bull.  18, 
4th  ser.,  p.  77,  1915. 


RESERVOIR  ROCKS  AND  COVERING  STRATA      63 

determinations  of  building  stones  of  Washington,  made  by  Shedd,1 
showed  an  average  porosity  of  13.7  per  cent. 

The  size  of  the  grains  of  a  sand  does  not  appear  to  limit  its 
porosity.  Some  of  the  productive  sands  of  the  Duke-Knowles  pool 
in  Texas  have  very  fine  grains.  In  many  parts  of  the  Sunset-Mid- 
way field,  California,  according  to  Pack,2  more  than  80  per  cent 
of  the  oil  sands  are  smaller  than  200  mesh.  Of  five  samples  of  oil 
sands  from  Russian  fields  treated  by  Thompson, 3  nearly  all  of  the 
material  passed  through  a  screen  measuring  80  meshes  to  the  inch 
and  all  of  one  sample  passed  through  one  measuring  200  meshes 
to  the  inch. 

Clay  particles  between  sand  grains  greatly  reduce  porosity.  The 
small  clay  particles  fill  the  pores  and  some  clay  is  in  a  jelly-like 
colloidal  state  which  is  relatively  impervious. 

Sands  grade  into  muds  and  sandstones  into  shales.  Muds  and 
shales  are  made  up  principally  of  very  fine  sand  grains  and  clay. 
Very  thin  sands  in  thick  series  of  shales  are  likely  to  be  filled  with 
clay  and  impervious  to  oil  and  water.  Some  of  the  sands  of  the 
Cretaceous  shale  and  sand  series  that  is  productive  in  Wyoming 
are  barren  at  places  in  northern  Montana,  where  the  thickness  of 
the  sands  decreases.  Sands  that  were  laid  down  far  out  from 
shore  lines  are  commonly  less  porous  than  sands  deposited  near 
shore. 

The  estimation  of  production  by  utilizing  saturation  as  a  factor 
has  been  worked  out  by  Washburne.4  He  estimates  that  the 
porosity  of  sand  ranges  from  0  to  20  per  cent  and  notes  that  field 
determinations  of  surface  samples  generally  show  lower  porosity 
than  those  of  buried  sands,  probably  because  near  the  surface 
calcium  carbonate  is  deposited  in  some  of  the  openings.  In  one 
determination  the  deep  sands  showed  one-fourth  greater  porosity 
than  the  same  sand  at  the  surface.  Washburne  estimates  for  two 
samples  60  and  75  per  cent  saturation,  the  volumetric  remainder, 
40  and  25  per  cent,  respectively,  being  assigned  to  gases  and  water. 
The  amount  of  oil  extracted  is,  according  to  Washburne,  60  to  80 

^HEDD,  SOLON:  Building  and  Ornamental  Stones  of  Washington.  Wash- 
ington Geol.  Survey  Ann.  Rept.,  1902,  vol.  2,  pp.  134-136,  1903. 

2PACK,  R.  W.:  The  Sunset-Midway  Oil  Field,  California.  U.  S.  Geol. 
Survey  Prof.  Paper  116,  p.  000,  1920. 

THOMPSON,  A.  B. :  Oil  Field  Development.     P.  107,  1916. 

WASHBURNE,  C.  W. :  Estimation  of  Oil  Reserves.  Am.  Inst.  Min.  Eng. 
Trans.,  vol.  51,  p.  645,  1915. 


64 


GEOLOGY  OF  PETROLEUM 


per  cent,  the  higher  figure  for  gas-rich  oils,  in  sands  pumped  to  a 
vacuum.     Heavy  asphaltic  oils  may  yield  considerably  less. 

The  porosity  of  porous  limestones  can  not  be  so  readily  estimated 
because  the  pores  in  limestone  are  more  diverse  in  size  and  not  so 
regularly  spaced.  Enlarged  sections  of  the  Trenton  limestone 
showing  the  nature  of  the  pores  are  illustrated  in  Fig.  12,  after 


FIG.  12. — Enlarged  sections  of  Trenton  limestone  showing  nature  of  pores. 

(After  Orton.) 


Orton.1  The  porosity  of  some  limestones  is  very  great.  The 
Trenton  limestone  and  the  Tamasopa  limestone  of  the  Tampico 
region  are  among  the  most  productive  oil-bearing  strata  known. 
The  Spindletop,  a  prolific  dome  in  Texas,  derived  its  oil  from  a 
porous  limestone. 

'ORTON,  EDWARD:  The  Trenton  Limestone  as  a  Source  of  Petroleum  and 
Inflammable  Gas  in  Ohio  and  Indiana.  U.  S.  Geol.  Survey  Eighth  Ann. 
Rept.,  part  2,  pp.  475-662,  1889. 


RESERVOIR  ROCKS  AND  COVERING  STRATA      65 

COVERINGS  OF  RESERVOIRS 

Kinds  of  Covering  Strata. — Nearly  all  the  strata  that  form  petro- 
liferous reservoirs  are  covered  by  argillaceous  rocks.  Paleozoic 
reservoirs  are  generally  covered  by  shales;  Mesozoic  reservoirs  by 
shales,  clays,  or  marls;  Cenozoic  reservoirs  by  clays  or  marls,  or, 
where  the  strata  have  become  indurated,  by  shales. 

In  the  Appalachian  field  of  the  United  States  the  covering  strata 
are  shales.  In  the  fields  of  southwestern  Ontario  the  strata  that 
cover  the  petroleum-bearing  limestone  are  soft  shales  or  "soap 
rock."  In  Ohio,  Indiana,  and  Illinois  the  reservoir  rocks  generally 
are  covered  by  shale.  In  the  Colmar  field,  Illinois,  the  Hoing  sand 
lies  as  patches  on  eroded  shale  and  is  covered  by  the  Niagara 
limestone.  In  Kentucky  and  Tennessee  the  reservoirs  are  covered 
by  shale,  but  in  parts  of  these  States  the  covering  shales  are  thin 
and  some  of  the  reservoirs  are  not  effectively  sealed. 

The  covering  strata  in  all  the  Kansas,  Oklahoma  and  northern 
Texas  fields  are  shales.  In  the  Balcones  fault  region  of  Texas  the 
reservoirs  are  covered  by  clays  and  marls.  In  the  northern  Louisi- 
ana fields  the  covering  strata  are  clays.  In  the  Gulf  coast  region 
of  Texas  and  Louisiana  the  covering  strata  are  clays,  muds,  and 
"gumbo." 

In  the  Rocky  Mountain  fields  the  covering  strata  are  shales, 
except  in  the  Douglas  field,  Wyoming,  where  a  little  oil  in  the 
White  River  formation  is  found  in  sandstone  below  clays.  In 
California  fields  the  covering  strata  are  shales  and  clays. 

In  the  Tampico  field,  Mexico,  the  deposits  in  the  Tamasopa 
limestone  are  covered  by  shales  and  clays.  The  petroliferous 
strata  of  Trinidad  are  covered  by  clays.  In  Peru  the  beds  covering 
the  oil  strata  are  shales. 

In  Alsace  the  petroliferous  sandstones,  according  to  Von  Wer- 
veke,  are  covered  by  marls.  In  the  Boryslaw  field,  Galicia,  the 
gas  and  oil-bearing  sandstones  of  the  Saliferous  formation  are 
covered  by  clay,  shale,  or  marl.  The  sands  and  conglomerates  of 
the  Dobrotow  (upper  Oligocene)  are  covered  by  shales.  In  the 
Schodnica  field  the  principal  petroliferous  members  are  thick  sand- 
stone lenses  in  clay.  In  the  Rumanian  fields  the  oil  and  gas  are  in 
sandstones  and  conglomerates  covered  by  marls,  clays,  and  shales. 
In  the  Baku  fields,  Russia,  the  oil  is  found  in  sands  covered  by 
clays  and  marls.  In  the  Grozny  field  the  sands  and  argillaceous 
cap  rock  are  said  to  be  more  indurated.  At  Maikop,  Russia,  the 


66 


GEOLOGY  OF  PETROLEUM 


reservoir  is  sand  covered  by  shale.  At  Holy  Island  the  reservoir  is 
a  sand  covered  by  clay.  In  the  Burma  fields  the  oil  sands  are 
covered  by  clay.  In  Java  the  oil  sands  are  covered  by  clay  and 
clayey  marls.  In  Japan  the  reservoirs,  which  consist  of  sandstone 
and  tuff,  are  covered  by  shale. 

Thickness  of  Covering  Strata. — The  thickness  of  the  covering 
that  is  necessary  to  retain  a  petroleum  deposit  depends  upon  the 
gas  pressure  that  exists  in  the  deposit.  If  the  covering  is  a  soft, 
pliable  rock  that  will  not  fracture  it  is  more  effective  than  an 

indurated,  brittle  or  jointed 

.1 

I- 


600- 


(Sew  Level 


FIG.  13. — Section  of  Oil  Springs  dome, 
Ontario,  showing  thin  cover  cap  holding  in 
oil  under  high  gas  pressure.  The  vertical 
scale  is  greatly  exaggerated.  (Based  on 
sketch  by  Williams.) 


rock.  Most  of  the  large  pe- 
troleum deposits  developed 
are  relatively  deep.  They 
are  held  down  by  adequate 
covers  of  clays  or  shales 
that  fracture  with  difficulty 
and  close  the  fractures  that 
are  made  in  them.  Some  oil 
fields,  however,  are  devel- 
oped very  near  the  surface. 
The  Drake  well  at  Titus- 
ville,  Pennsylvania,  encoun- 
tered oil  at  a  depth  of  only 
69  feet  and  yielded  oil  at  the  rate  of  25  barrels  daily.  Flowing  wells 
have  been  brought  in  less  than  100  feet  below  the  surface.  A  well- 
known  shallow  oil  field  is  the  one  in  Lambton  and  Middlesex 
Counties,  southwestern  Ontario  (Fig.  13).  The  producing  stratum 
is  the  porous  limestone,  which  is  covered  by  about  400  feet  of 
shales,  limestone,  and  glacial  drift.  The  shales  are  soft  and  very 
pliable  and  are  referred  to  by  the  drillers  as  "soapstone."  Flowing 
wells  shooting  high  in  the  air  and  producing  from  3,000  to  6,000 
barrels  a  day  each  were  obtained  in  this  field.  The  efficiency  of 
the  thin  covering  is  due  probably  to  the  nature  of  the  rocks,  the 
limestone  layers  giving  strength  to  the  whole  and  the  soft  shales 
sealing  any  opening  that  may  have  formed. 

The  Llewellyn  well,  100  feet  deep,  which  flowed  oil  at  the  rate  of 
1,000  to  2,000  barrels  a  day,  was  opened  in  the  early  sixties  on  the 
Eureka  Springs  anticline  in  West  Virginia.1 

DULLER,  M.  L. :  Appalachian  Oil  Field.  Geol.  Soc.  America  Bull,  vol.  28, 
p.  623, 1917. 


RESERVOIR  ROCKS  AND  COVERING  STRATA       67 

TYPICAL  RECORD  OF  A  WELL  IN  OIL  SPRINGS  POOL,  LAMBTON  COUNTY, 

ONTARIO 

Pleistocene :  Feet 

Surface 0-  60 

Hamilton: 

Upper  limestone 60-  95 

Upper  "soapstone" 95-196 

Middle  limestone 196-223 

Lower  "soapstone"  (salt  water  at  252  feet) 223-330 

Onondaga : 

Lower  limestone  (oil  at  370  feet) 330-370 

Shallow  wells  encounter  oil  in  the  Irvine  district,  Kentucky, 
where  a  porous  limestone  forms  the  reservoir.  It  is  overlain  by  the 
black  shale  of  the  Chattanooga  formation  (Upper  Devonian). 
This  shale  is  higher  in  the  geologic  column  than  the  Hamilton, 
which  is  the  covering  of  the  "Corniferous"  limestone  in  Ontario. 
It  is  also  more  brittle,  although  where  sufficiently  thick  it  supplies 
a  good  cap  rock.  In  this  region  wells  only  80  or  90  feet  deep  sunk 
in  the  shales  and  penetrating  the  limestone  have  obtained  oil. 
Unlike  the  oil  in  the  Ontario  field,  however,  it  was  not  under  a  high 
gas  pressure.1 

Oil  was  found  at  comparatively  shallow  depths  in  the  eastern 
part  of  the  Kansas-Oklahoma  field,  and  also  at  Brownwood  and 
Strawn,  Texas.  In  these  regions  where  the  oil-bearing  strata  are 
shallow  in  general  the  pressures  and  the  initial  production  are  low. 
In  the  great  Mid-Continent  gusher  fields  the  coverings  are  in 
general  comparatively  thick. 

'SHAW,  E.  W. :  The  Irvine  Oil  Field,  Estill  County,  Kentucky.  U.  S.  Geol. 
Survey  Bull.  661,  p.  145,  1918. 


CHAPTER  VI 
SOME  PROPERTIES  OF  PETROLEUM  AND  GAS 

Color. — Most  crude  oils  are  opaque  except  in  very  thin  bodies. 
As  a  rule  the  color  of  thin  layers  in  light  passed  through  them  is 
brown,  although  some  oils  are  red  and  others  yellow.  The  light 
oil  obtained  in  the  Calgary  field,  Alberta,  is  a  pale  lemon-yellow. 
A  little  white  oil  has  been  found  in  the  Los  Angeles  field,  Cali- 
fornia, and  considerable  quantities  of  pale  straw-colored  or  "white" 
oil  are  recovered  in  the  Surakhany  field1  in  the  Baku  region, 
Russia.  White  oils  are  supposed  to  result  from  the  natural  filtra- 
tion of  petroleum  through  clay.  Sumatra,  according  to  Thomp- 
son,2 yields  large  quantities  of  volatile  crude  oil  having  the  color 
of  port  wine. 

By  reflected  light  most  crude  oils  have  a  greenish  cast.  Some, 
however,  are  yellow  or  black,  or  of  the  same  color  as  when  seen  in 
transmitted  light.  The  greenish  cast  of  crude  oil  in  reflected  light 
frequently  serves  to  distinguish  it  from  some  products  of  refining, 
which  have  a  bluish  fluorescence.3 

Odor. — Oils  from  different  fields  have  different  and  fairly  con- 
stant odors.  The  Pennsylvania  oils  smell  like  gasoline.  Cali- 
fornia oils,  which  have  less  odor,  smell  like  coal  tar.  Some  East 
Indian  oils  smell  like  oil  of  cedar.  The  Lima-Indiana  oil  has  the 
disagreeable  odors  of  sulphur  compounds. 

The  odors  of  oils  have  been  used  to  assist  in  ascertaining  their 
origin.  According  to  Clapp, 4  in  order  to  determine  the  character- 
istic odor  of  an  oil,  samples  should  be  prepared  in  narrow  bottles, 
stoppered,  half  filled  with  the  oil.  The  oil  is  shaken  vigorously 
so  as  to  impart  its  odor  to  the  air  above  the  oil  in  the  bottle,  and 
if  this  gives  the  odor  of  hydrogen  sulphide,  a  strong  solution  of 
caustic  potash  is  added  and  the  oil  shaken  until  the  odor  of  sulphide 

THOMPSON,  A.  B. :  The  Oil  Fields  of  Russia.     P.  94,  London,  1904. 
THOMPSON,  A.  B.:  Oil-field  Development.     P.  278,  1916. 
'CLAPP,  F.  G. :  Petroleum  and  Natural  Gas  Resources  of  Canada.     Vol.  1, 
p.  45,  Canada  Dept.  Mines,  1914,  Mines  Branch. 
4CLAPP,  F.  G.,  op.  cit.,  p.  47. 

68 


SOME  PROPERTIES  OF  PETROLEUM  AND  GAS      69 

of  hydrogen  disappears.  Many  California  oils,  shaken  with 
caustic  potash  solution  will  give  an  odor  of  pyridine.  In  a  second 
sample  the  odor  should  be  noted  after  similar  treatment  with 

dilute  sulphuric  acid. 

DENSITY 

The  value  of  an  oil  in  a  general  way  is  suggested  by  its  weight, 
or  specific  gravity.  As  a  rule  light  oils  will  yield  larger  proportions 
of  the  more  valuable  products,  such  as  gasoline  and  kerosene. 
The  heavier  products  are  used  in  the  main  for  fuel  and  for  road 
dressing  and  are  lower  priced.  If,  however,  the  heavy  oil  contains 
considerable  paraffin  wax  or  materials  that  can  be  used  for  lubri- 
cants it  may  bring  a  higher  price  than  light  oil.  The  highest- 
priced  oils  are  natural  lubricating  oils.  These  are  comparatively 
rare  and  are  generally  produced  from  shallow  wells  of  small 
yield. 

The  specific  gravity  of  an  oil  is  its  weight  divided  by  that 
of  the  weight  of  the  same  volume  of  distilled  water,  taken  as 
1.000.  By  this  standard  oils  range  in  weight  from  0.780  or  less 
to  1.000.' 

In  foreign  countries  the  decimal  specific-gravity  scale  is  exten- 
sively used,  but  in  the  United  States  the  Baume  scale  is  used  almost 
exclusively.  That  is  an  arbitrary  scale  in  which  the  weight  of 
water  is  placed  at  10°,  the  degrees  increase  as  the  weight  of  the 
liquid  decreases.  Thus,  the  lighter  an  oil  the  higher  the  number 
on  the  Baume  scale.  The  United  States  Bureau  of  Standards 
uses  the  following  formula1  for  converting  degrees  Baume  into 
the  decimal  standard: 

140 

°Baume  = 130 

Specific  gravity  of  liquid 

The  density  is  taken  at  60°  F. 

On  p.  70  is  a  table  to  be  used  for  converting  readings  from  one 
scale  to  the  other  and  from  pounds  per  gallon,  barrel,  or  cubic  foot 
to  either  scale.  Gravity  determinations  are  made  by  weighing  a 
known  volume  of  the  oil  either  in  a  large  container  or  on  an  assay 
balance  in  a  small  weighing  bottle,  or  by  placing  the  hydrometer 
in  the  oil  and  reading  off  the  scale. 

1Used  for  liquids  lighter  than  water. 


70 


GEOLOGY  OF  PETROLEUM 


EQUIVALENTS  OP  BAUM£  SCALE  AND  SPECIFIC  GRAVITY 
(After  Payne  and  Stroud) 


Deg. 
Be. 

Specific 
Gravity 

WEIGHT,  POUNDS 

Deg. 
Be. 

Specific 
Gravity 

WEIGHT,  POUNDS 

Per 
Gallon 

Per 
Barrel 

Per 

Cubic 
Foot 

Per 
Gallon 

Per 
Barrel 

Per 
Cubic 
Foot 

10 

1.0000 

8.328 

349.79 

62.301 

36 

0.8434 

7.024 

295.02 

52.545 

11 

0.9929 

8.269 

347.31 

61.859 

37 

0.8383 

6.982 

293.23 

52.227 

12 

0.9859 

8.211 

344.86 

61.422 

38 

0.833? 

6.940 

291.48 

51:915 

13 

0.9790 

8.153 

342.45 

60.993 

39 

0.8284 

6.899 

289.77 

51.610 

14 

0.9722 

8.097 

340.07 

60.569 

40 

0.8235 

6.858 

288.05 

51.305 

15 

0.9655 

8.041 

3.3772 

60.152 

41 

0.8187 

6.818 

286.38 

51.006 

16 

0.9589 

7.986 

335.42 

59.740 

42 

0.8140 

6.779 

284.73 

50.713 

17 

0.9524 

7.932 

333.14 

59.335 

43 

0.8092 

6.739 

283.05 

50.414 

18 

0.9459 

7.878 

330.87 

58.931 

44 

0.8046 

6.701 

281.44 

50.127 

19 

0.9396 

7.825 

328.67 

58.538 

45 

0.8000 

6.663 

279.83 

49.841 

20 

0.9533 

7.773 

326.46 

58.145 

46 

0.7955 

6.623 

278.26 

49.560 

21 

0.9272 

7.722 

324.33 

57.765 

47 

0.7910 

6.588 

276.68 

49.280 

22 

0.9211 

7.671 

322.19 

57.385 

48 

0.7865 

6.550 

275.11 

48.999 

23 

0.9150 

7.620 

320.06 

57.005 

49 

0.7821 

6.514 

273.57 

48.726 

24 

0.9091 

7.571 

317.99 

56.637 

50 

0.7778 

6.478 

272.07 

48.458 

25 

0.9032 

7.522 

315.93 

56.270 

51 

0.7735 

6.442 

270.56 

48.189 

26 

0.8974 

7.474 

313.90 

55.909 

52 

0.7692 

6.406 

269.06 

47.922 

27 

0.8917 

7.426 

311.91 

55.554 

53 

0.7650 

6.371 

267.59 

47.660 

28 

0.8861 

7.379 

309.95 

55.205 

54 

0.7609 

6.337 

266.16 

47.405 

29 

0.8805 

7.339 

307.99 

54.856 

55 

0.7568 

6.303 

26.472 

47.149 

30 

0.8750 

7.287 

306.07 

54.513 

56 

0.7527 

6.269 

263.29 

46.894 

31 

0.8696 

7.242 

304.18 

54.177 

57 

0.7487 

6.235 

261.89 

46.644 

32 

0.8642 

7.197 

302.29 

53.840 

58 

0.7447 

6.202 

260.49 

46.395 

33 

0.8589 

7.153 

300.44 

53.510 

59 

0.7407 

6.169 

259.09 

46.146 

34 

0.8537 

7.110 

298.62 

53.186 

60 

0.7368 

6.136 

257.73 

45.903 

35 

0.8485 

7.066 

296.80 

52.862 

61 

0.7330 

6.105 

256.40 

45.667 

SOME  PROPERTIES  OF  PETROLEUM  AND  GAS      71 


Oil  expands  with  increase  in  temperature.     The  coefficients  of 
expansion  of  certain  oils  are  shown  in  the  following  table: 

COEFFICIENTS  OF  EXPANSION  OF  SOME  OILS 
(After  Hoefer) 


Density  ) 

<  1,000  at 

Coefficient  of 
Expansion 

Origin 

0  Dcg.  C. 

50  Dcg.  C. 

X  100,000 

West  Virginia  (Burning  Spring)  .  .  . 
Pennsylvania  (Oil  Creek)  .  . 

841 

816 

808 

784 

81 

82 

Canada     

870 

851 

44 

Burma     .  .          

892 

861 

72 

Russia  (Baku) 

954 

920 

71 

Eastern  Galicia  
Western  Galicia     .  . 

870 
855 

836 
852 

81 

77 

Rumania  (Ploiesti) 

862 

829 

80 

Italy  (Parma,  Neviano  de  Rossi).  .  . 
Hanover  (Oberg) 

809 
944 

772 
914 

96 
66 

Alsace  (Pechelbronn)   
France  (St.  Gabian) 

912 

894 

880 
861 

73 

69 

Zante 

952 

921 

67 

Viscosity.  —  The  viscosity  of  oil  varies  with  its  specific  gravity. 
It  is  measured  by  ascertaining  the  time  it  takes  a  given  amount  of 
the  oil  to  flow  through  a  small  opening  in  a  viscosimeter.  The 
instruments  used  are  the  Engler  viscosimeter  and  the  Saybolt 
viscosimeter.  A  unit  often  used  is  the  Engler  unit,  obtained  by 
dividing  the  time  of  the  outflow  of  200  cubic  centimeters  of  the 
oil  by  the  time  of  outflow  of  the  same  quantity  of  water  at  20°  C. 

The  determinations  are  of  interest  especially  to  pipe-line  com- 
panies and  all  others  who  transport  oil  through  pipes.  Some  oils 
are  so  thick  that  it  is  found  practicable  to  heat  them  to  decrease 
their  viscosity.  The  lubricating  properties  of  oils  are  closely 
related  to  their  viscosity. 

Composition  of  Petroleum.  —  Petroleums  are  mixtures  of  com- 
pounds of  carbon  and  hydrogen,  generally  with  impurities  con- 
sisting of  sulphur  compounds  and  nitrogen  compounds.  Hydro- 
carbons of  the  following  series  have  been  discovered  in  petroleum.1 


CH 


n2n 


CnH 


CnH2n  _  4 

H.:   Das  Erdol.    P.  54,  1906. 


72 


GEOLOGY  OF  PETROLEUM 


The  compounds  most  frequently  appearing,  according  to  Hoefer, 
belong  to  the  first  or  paraffin  series,  the  second  or  olefine  series, 
and  the  fifth  or  aromatic  (benzene)  series.  Of  these  the  paraffins 
are  much  the  most  abundant  in  both  natural  gas  and  petroleum. 
The  sulphur  compounds  in  oil  are  mentioned  on  page  85,  and  the 
nitrogen  compounds  on  page  82. 

PARAFFINS  FROM  PETROLEUM* 


Name 

Formula 

Melting 
Point 

Boiling 
Point 

1.  Gaseous: 
Methane  
Ethane 

CH4 

C2H6 

Deg.  C. 

-184 
-172.1 

Deg.  C. 
-164 
-  84.1 

Propane  
Butane                      

C3H8 

-  45 

-  45.0 
+     1 

2.  Liquid: 
Pentane 

36.3 

Hexane       

C6H14 

69 

Heptane 

98 

Octane   

125.8 

Nonane 

-  51 

150 

Decane           

CiO-H.22 

-  31 

173 

Endecane 

-  26 

195 

Dodecane              

C  1  2-H  2  6 

-  12 

214 

Tridecane 

G 

234 

Tetradecane       

+     4 

252 

Pentadecane 

-  10 

270 

Hexadecane                

C  1  6-H  3  4 

18 

287 

Heptadecane                    .   . 

Grilse 

22 

303 

3.  Solid: 
Octodecane 

28 

317 

Eicosane     .... 

C2oH-42 

37 

Tricosane 

48 

Tetracosane 

50-51 

Pentacosane 

53-54 

55-56 

Octocosane 

60 

Nonocosane 

62-63 

66 

Dotriacontane 

67-68 

Tetratriacontane  
Pentatriacontane 

C34-H.70 

71-72 
76 



'After  HOEFER,  H.:  Op.  cit.,  pp.  58-59,  with  additions  and  changes. 


SOME  PROPERTIES  OF  PETROLEUM  AND  GAS      73 

Oils  are  commonly  classified  as  those  with  asphaltic  base  and 
those  with  paraffin  base.  Asphaltic  oils  are  those  that  yield  on 
distillation  a  dark  asphaltic  residue.  Paraffin  oils  on  distillation 
yield  light-colored  paraffins  that  do  not  dissolve  in  the  solvents 
that  dissolve  asphalts.  Oils  that  contain  paraffin  are  more  easily 
refined  than  those  that  contain  asphalt.  In  general  asphaltic  oils 
sell  at  a  lower  price  than  paraffin  oils.  Many  oils,  including  most 
mid-continent  and  Rocky  Mountain  oils,  contain  both  asphalt  and 
paraffin. 

In  ordinary  work  oil  is  analyzed  to  ascertain  what  fractions  may 
be  obtained  from  it  by  distillation,  rather  than  exactly  what  chem- 
ical compounds  are  present.  The  standard  method  of  analysis, 
known  as  Engler's  method,  has  been  recommended  by  the  Third 
International  Petroleum  Congress.  This  method  is  described  by 
Day1  as  follows.  One  hundred  cubic  centimeters  of  the  crude  oil, 
measured  at  60°  F.,  is  delivered  by  a  pipette  into  a  distilling  bulb 
holding  about  125  cubic  centimeters.  The  thermometer  used  is  a 
nitrogen  thermometer,  reading  to  550°  C.  The  condenser  tube, 
as  prescribed  by  Engler,  is  75  centimeters  long  and  has  an  inclina- 
tion of  75°  from  the  horizontal.  The  point  of  initial  boiling  is 
taken  when  the  first  drop  of  oil  falls  from  the  condenser  tube  into 
the  receiving  flask.  To  avoid  loss  by  evaporation  the  condenser 
tube  is  ground  to  fit  into  the  graduated  receiving  flask,  which  is 
provided  with  a  stopcock  to  draw  off  the  oil  at  150°  C.  and  again 
at  300°  C.  The  fraction  between  the  initial  boiling  point  and  150° 
C.  (302°  F.)  constituting  the  gasoline  fraction,  and  the  fraction 
between  150°  and  300°  C.  (572°  F.),  constituting  the  kerosene 
fraction,  are  examined  for  specific  gravity.  The  residuum  is 
weighed  as  soon  as  cool;  then  its  specific  gravity  is  taken  in  the 
usual  way  and  the  volume  calculated.  The  total  thus  obtained 
for  the  different  fractions  includes  the  sum  of  all  determinations. 

^AY,  D.  T. :  The  Production  of  Petroleum  in  1913.  U.  S.  Geol.  Survey 
Mineral  Resources,  1913,  part  2,  p.  1123,  1914. 


74 


GEOLOGY  OF  PETROLEUM 

ANALYSES  OF  PETROLEUMS™ 


LOCATION 

Depth 
of  Well, 
Feet 

PHYSICAL  PROPERTIES 

GRAVITY  AT  60  DEG. 
F. 

Color 

Odor 

Specific 

Baume 

1    Petrolia,  Ontario,  Lambton  County  . 
2    Venango  County,  Pennsylvania  .... 
3    Petroleum,  Allen  County,  Kentucky 
4    Parkersburg,  Wood  County,  West 
Virginia  

810 

350 
2,462 

0.8580 
0.8820 
0.8490 

0.8750 
0.7848 

0.8284 
0.8289 
0.8790 
0.8647 
0.8459 

0.9352 
0.8065 
0.9590 
0.9673 
0.8480 

0.8800 
0.8460 

33.0 
28.7 
34.9 

30.0 
48.4 

39.0 
38.9 
29.3 
31.9 
35.5 

19.7 
43.6 
16.0 
14.7 
35.0 

29.0 
35.0 

Dark  brown 
Brown 

Dark  green 
Medium  green 

Like  Pennsylvania  oil 

Like  Pennsylvania  oil 
Like  Pennsylvania  oil 

Sulphur 

5    Bremen  pool,  Fairfield  County,  Ohio 
6    Northwestern  Ohio—  Trenton  lime- 
stone   

7    Lawrence  County,  Illinois  
8    Terre  Haute,  Vigo  County,  Indiana. 
9    Chanute  pool,  Allen  County,  Kansas 
10    Glenn  pool,  Creek  County,  Oklahoma 
11    Sour  Lake  pool,  Hardin  County, 
Texas  
12    Caddo  pool,  Marion  County,  Texas  . 
13    Coalinga,  Fresno  County,  California. 
14    Kern  River,  Kern  County,  California 
15    Zorritos,  Peru 

1,700 

751 
1,500 

1,020 
=±=2,300 

Dark  green 

Dark  green 
Black 

Dark  green 
Brown 

Black 
Dark  brown 

Sulphur 
Like  Pennsylvania  oil 

16    Baku  Russia 

17    Rumania 

°In  the  preparation  of  this  table  I  have  used  data  compiled  by  F.  G.  CLAPP. 

1.  REDWOOD,  BOVERTON:  Treatise  on  Petroleum.     Vol.  1,  p.  228. 

2.  HENRY,  J.  T.:  History  of  Petroleum.     B.  Silliman,  analyst. 

3.  4,  5,  7,  11,  12.     DAY,  D.  T.:  U.  S.  Geol.  Survey  Mineral  Resources,  1909,  part  2. 
6.  ORTON,  EDWARD:  U.  S.  Geol.  Survey  Eighth  Ann.  Rept.,  part  2,  1889. 

8.  Indiana  Dept.  Geology  and  Nat.  Resources.     W.  A.  Noyes,  analyst. 

Composition  of  Natural  Gas. — Natural  gas  is  associated  with 
practically  all  petroleums.  It  rises  to  the  higher  points  of  reser- 
voirs, and  it  is  absorbed  in  the  oil.  Under  the  high  pressures  that 
exist  in  some  fields  considerable  quantities  are  absorbed.  Expan- 
sion of  gas  pushes  the  oil  out  of  the  interstices  of  the  rocks  and 
causes  it  to  flow  in  wells.  It  is  the  gas  pressure  that  causes  wells 
to  spout  oil  and  salt  water.  Even  in  wells  that  are  pumped,  the 
gas  generally  forces  the  oil  to  the  boring. 


SOME  PROPERTIES  OF  PETROLEUM  AND  GAS      75 

ANALYSES  OF  PETROLEUMS" 


DISTILLATION  BT  ENGLER'S  METHOD,  BY  VOLUME 

UNSATERATED 
HYDRO- 

To 150  Deg.  C. 

150  Deg.-300 
Deg.  C. 

Residuum 

Sul- 
phur, 

Par- 
affin, 

As- 
phalt, 

Water, 

CARBONS, 
PER  CENT 

Total 

per 

per 

per 

per 

Cubic 

Cent 

Cent 

Cent 

Cent 

150 

Cubic 

Specific 

Cubic 

Specific 

Cubic 

Specific 

Centi- 

Crude 

Deg.- 

Centi- 

Grav- 

Centi- 

Grav- 

Centi- 

Grav- 

meters 

300 

meters 

ity 

meters 

ity 

meters 

ity 

Deg. 

2.50 

57.50 

°40.00 

100.00 

8.55 

42.78 

48.67 

100.00 

12.50 

0.7373 

41.00 

0.8144 

45.30 

0.9162 

98.80 

3.65 

2.10 

Trace 

18.8 

7.0 

16.00 

0.8356 

82.40 

0.8872 

98.40 

Much 

21.6 

5.0 

15.00 

0.7036 

40.00 

0.7698 

42.00 

0.8557 

97.00 

8.  -33 

None 

11.6 

4.0 

15.00 

33.00 

51.46 

0.54 

... 

... 

.... 

12.00 

0.7230 

35.00 

0.7874 

49.20 

0.9067 

96.20 

4.31 

Trace 

39.60 

0.8254 

60.40 

100.00 

0  72 

5.00 

0.7350 

36.00 

0.7993 

57.80 

0.9223 

98.80 

4.25 

1.23 

8.50 

0.7566 

42.00 

0.8001 

49.90 

0.9032 

100.40 

6.98 

0.45 

23.00 

0.8750 

76.70 

0.9569 

99.70 

59.6 

.11.0 

6.00 

0.7305 

50.50 

0.7646 

42.90 

0.8739 

99.40 

7.02 

12.8 

5.0 

14.50 

85.50 

100.00 

9.50 

100 

28.99 

71.01 

100.00 

0.95 

21.25 

... 

25.00 

28.50 

17.00 

31.00 

... 

35.00 

0.63 

0.7620 

37.28 

62.09 

100.00 

.... 

10.00 

81.88 

5.89 

97.77 

2.23 

9,  10.     DAY,  D.  T.:  U.  S.  Geol.  Survey  Mineral  Resources,  1909,  part  2. 

13.  U.  S.  Geol.  Survey,  from  card  reporting  production. 

14.  Am.  Chem.  Soc.  Jour.,  vol.  25.     Edmond  O'Neil,  Univ.  California,  analyst. 

15.  U.  S.  Geol.  Survey  Mineral  Resources,  1909,  part  2.     American  Analysis  &  Chemical 
Co.,  analyst. 

16.  17.  REDWOOD,  BOVEBTON,  op.  cit.,  p.  225. 

Although  practically  all  oils  are  associated  with  inflammable 
gas,  there  are  at  many  places  issues  of  gas  that  are  not  associated 
with  oil.  The  gas  that  forms  in  swamps  and  marshes  has  been 
mentioned  (p.  33).  In  Minnesota,  in  sands  below  glacial  clay, 
gas  is  found  in  quantities  sufficient  for  lighting  houses  and  under 
a  pressure  as  great  as  12  pounds  to  the  square  inch.  Swamp  gas 
is  generally  methane  or  "marsh  gas."  Analyses  of  natural  gases 


76 


GEOLOGY  OF  PETROLEUM 


are  shown  in  the  accompanying  tables.1     Properties  of  some  of  the 
lighter  hydrocarbons  are  given  in  the  table  following  the  analyses. 

ANALYSES  OF  NATURAL  GAS  (Table  Prepared  by  F.  E.  Carter) 


Meth- 
ane 
(CH<) 

Eth- 
ane 
(C2H6) 

Carbon 
Diox- 
ide 
(C02) 

Oxygen 
(02) 

Nitro- 
gen 
(Ms) 

Other  Gases 

Authority 

Ontario 

92  6 

0  3 

0  3 

3  6 

H2,  2.2;  CO 

Tassarts0 

Vancouver,  British  Columbia.  . 
Calgary,  Alberta  
United  States: 
Wyoming 

91.6 
81  7 

93.6 
17  4 

0.1 
0  2 

0.2 

6.3 

8.2 

0  7 

0.5;  H2S, 
0.2;    C2H4, 
0.3 

Phillips6 
Carterc 

Burrell<* 

Pennsylvania 

92  6 

0  3 

7  1 

Phillips' 

New  York 

90  1 

0  4 

Trace 

9  5 

Phillips' 

Cleveland,  Ohio 

93  5 

0  2 

6  3 

Phillips 

Indiana 

77  4 

14  2 

0  7 

6  6 

C2H<,0.9; 

Cady  and 

Kansas 

90  6 

1  0 

0  6 

7  1 

He,  0.2 
C2H4,  0.2; 

McFarland" 
Do. 

California        ' 

83  7 

6  7 

2  8 

6  3 

CO,  0.5 
C2H4,  0.2; 

Do. 

Russia: 
Ssurachany 

94  0 

4  0 

0  4 

0  6 

CO,  .3 
C2H4,  1.0 

V.Herr* 

Bibi-Eibat 

86  3 

2  8 

10  0 

0  2 

0  7 

Do. 

Baku 

91  2 

1  3 

1  8 

1  2 

4  5 

Do. 

Galicia: 
Tustanowice 

86  5 

1  0 

3  8 

Heavy  hydro- 

Grusciewicz 

Hungary: 

Seibenburgen 

91  0 

0.2 

0.3 

1  4 

carbons, 
8.7 

Eeavy  hydro- 

and Haus- 
mann* 

Zeller* 

99  0 

0.4 

0.2 

carbons, 
1.1;  unstat- 
ed, 6.0 
H2,  0.4 

Czako* 

"Exploit  du  Petrol,  1908,  p.  302. 

&Am.  Chem.  Jour.,  vol.  16,  p.  416,  1894. 

cFuel-testing  Division,  Mines  Branch,  Ottawa. 

<*Bur.  Mines  Tech.  Paper  57. 

«Am.  Chem.  Jour.  vol.  16,  p.  416,  1894. 

/Chem.  Centralblatt,  1887,  p.  1524. 

a  Jour.  Am.  Chem.  Soc.,  vol.  29,  p.  1523,  1907. 

ATrudy,  1908. 

^Petroleum,  vol.  6,  p.  2245,  1911. 

^Petroleum,  1906,  p.  297. 

I  Jour.  Gasbeleuchtung,  December,  1911. 

aSee  also  CADY,  H.  P.,  and  MCFARLAND,  D.  F. :  Chemical  Composition  of 
Gas.     Kansas  Geol.  Survey,  vol.  9,  pp.  228-302,  1908. 


SOME  PROPERTIES  OF  PETROLEUM  AND  GAS      77 

ANALYSES  OP  NATURAL  GAS* 


Gross 

Heating 

Value  per 

Specific 

Total 

Cubic  Foot 

Grav- 

Oil Field 

County 

State 

CO* 

Oj 

N2 

Par- 

Total 

CH4 

CzHe 

at  0°  C. 

ity 

affins 

and  760 

(air- 

Millimeters 

1) 

Pressure 

Santa  Maria. 

Santa  Barbara 

California 

15.5 

0.2 

1.4 

82.9 

100.0 

62.7 

20.2 

B.t.u. 
1,044 

0.81 

Torrey  

Ventura 

California 

6.8 

0.0 

3.4 

89.8 

100.0 

54.2 

35.6 

1,240 

0.81 

Coalinga  

Fresno 

California 

11.1 

0.0 

0.9 

88.0 

100.0 

88.0 

0.0 

937 

0.66 

McKittrick.  . 

Kings 

California 

30.4 

0.0 

2.4 

67.2 

100.0 

66.2 

1.0 

724 

0.85 

West  Los 

Angeles..  . 

Los  Angeles 

California 

1.0 

0.1 

5.2 

93.7 

100.0 

91.0 

2.7 

1,019 

0.60 

Sunset  

Kings 

California 

10.5 

0.0 

1.8 

87.7 

100.0 

87.7 

0.0 

934 

0.66 

Fullerton  

Orange 

California 

1.7 

0.0 

2.1 

96.2 

100.0 

86.7 

9.5 

,100 

0.63 

Kern  River.  . 

Kern 

California 

6.5 

0.0 

1.2 

92.3 

100.0 

84.3 

8.0 

,047 

0.66 

Clarion 

Pennsyl- 

0.0 

0.0 

1.1 

98.8 

100.0 

96.4 

2.5 

,073 

0.57 

vania 

Forest 

Do. 

0.0 

0.0 

1.0 

99.0 

100.0 

70.8 

28.2 

,279 

0.70 

Clarion 

Do. 

0.0 

0.0 

1.7 

98.3 

100.0 

80.5 

17.8 

,189 

0.65 

Butler 

Do. 

0.0 

0.0 

0.9 

99.1 

100.0 

53.3 

45.8 

,420 

0.78 

Armstrong 

Do. 

0.05 

0.0 

1.45 

98.5 

100.0 

81.6 

16.9 

,184 

0.64 

Hogshooter.  . 

Osage 

Oklahoma  ' 

1.1 

0.0 

4.6 

94.3 

100.0 

94.3 

0.0 

,004 

0.58 

Creek 

Oklahoma 

2.4 

0.0 

1.8 

95.8 

100.0 

64.1 

31.7 

,273 

0.74 

Barren 

Kentucky 

2.5 

0.0 

1.3 

93.3 

6100.0 

23.6 

69.7 

,548 

0.91 

Barren 

Kentucky 

2.6 

0.0 

5.1 

92.3 

C100.0 

44.1 

48.2 

,367 

0.84 

Grand 

Utah 

3.6 

0.0 

5.6 

90.8 

100.0 

90.8 

0.0 

967 

0.61 

Grand 

Utah 

3.5 

0.0 

6.5 

90.0 

100.0 

90.0 

0.0 

959 

0.62 

«Bur.  Mines  Bull.  88,  p.  21,  1915. 
&H2S,  2.9  per  cent. 
<H2S,  0.1  per  cent. 

The  recovery  of  gasoline  from  natural  gas  has  become  an  im- 
portant industry.  By  one  method  the  gasoline  is  recovered  by 
condensation  of  the  gas;  by  another  it  is  recovered  by  absorption 
of  the  gasoline  when  the  gas  is  passed  through  a  heavy  oil.  The 
gasoline  is  in  great  demand  for  mixing  with  low-grade  naphtha. 
In  1911  176  plants  in  nine  States  produced  7,425,839  gallons  of 
gasoline  from  natural  gas.  In  1917,  only  six  years  later,  886  plants 
in  12  States  produced  217,884,104  gallons.  Prior  to  1916  the 
greater  portion  of  the  gasoline  recovered  from  natural  gas  was 
obtained  by  methods  involving  compression  and  condensation. 
Since  1913,  however,  a  steadily  increasing  proportion  of  the  annual 
output  of  natural-gas  gasoline  has  been  recovered  by  the  absorp- 
tion process.  The  development  of  this  process  that  followed  work 


78 


GEOLOGY  OF  PETROLEUM 


done  by  G.  M.  Sabolt  has  extended  the  scope  of  the  natural  gas 
gasoline  industry  to  include  types  of  natural  gas  containing  too 
little  gasoline  to  warrant  their  successful  treatment  by  compression 
methods.1  Some  gasoline  is  recovered  also  from  "drips"  in  pipe 
lines  that  carry  gas. 

PROPERTIES  OF  SEVEN  PARAFFIN  HYDROCARBONS" 


QQ 

S§ 

||| 

^3 

1 

| 

-0 

1 

II 

•1*9 

1 

D  *"*• 

J 
| 

III 

-SO 

||| 

g- 

B 

M 

a 

|| 

^ 

"c«o    ^ 

"3 

>  §^ 

—  S*3 

i 

to 

1 

1 

^•5 

1 

"rto     § 

Is! 

s 

£ 

'^  ^ 

a 

is! 

o  i 

CO  * 

«£ 

33* 

II 

British 

Candle- 

C. 

Grams 

B.t.u. 

power 

Cu.Ft. 

Methane  ..  . 

CH« 

—  164d 

0.554 

0.7159 

1,065 

e5.0 

9.57 

Ethane 

C2H« 

-  84.  \d 

1.049 

1.3567 

1,861 

A35.0 

53 

16.72 

Propane     .  • 

CaHs 

-  45d 

1.520 

1.9660 

2,654 

A53.9 

45 

23.92 

Butane  

2.004 

2.594 

3,447 

37 

31.10 

Pentane  

C6Hl2 

36  .'4* 

4,250 

31 

38.28 

Hexane  

CeHu 

68.9* 

5,012 

27 

Heptane  

C?Hl6 

98.4* 

"Bur.  Mines  Bull.  88,  1915. 

&HOLLEMAN,  A.  F.:  Organic  Chemistry,  edited  by  A.  J.  Walker.     P.  41,  1910. 
^LANDOLT  and  BORNSTEIN:  Physikalisch-chemische  Tabellen,  3d  ed.     Pp.  416,  425,  1905. 
(J.  Thomsen.) 

<*Gas  at  ordinary  temperature. 

«WRIGHT,  L.  T.:  Illuminating  Power  of  Methane.     Chem.  Soc.  Jour.,  vol.  47,  p.  200,  1885. 
/LANDOLT  and  BORNSTEIN:  Physikalisch-chemische  Tabellen,  3d  ed.  P.  185,  1905.   (Dewar.) 
oldem.     (Olzewski.) 

,  P.:  Illuminating  Power  of  Methane.     Jour.  Chem.  Soc.,  vol.  47,  1885,  p.  235. 

BORNSTEIN:  op.  cit.,  D.  182.     (Dewar.) 
^Liquid  at  ordinary  temperature. 

NORTHROP,  J.  D. :  Gasoline  from  Natural  Gas.     U.  S.  Geol.  Survey  Min- 
eral Resources,  1917,  part  2,  p.  1115,  1919. 


SOME  PROPERTIES  OF  PETROLEUM  AND  GAS      79 

NATURAL-GAS  GASOLINE  MARKETED  IN  THE  UNITED  STATES  IN  1917a 


PLANTS 

GASOLINE  PRODUCED 

h 

*J3 

"8  | 

J  8 

||l 

State 

•Sfi 

«t£ 

^  a 

Daily 

Price 

3 

&  £"§ 

* 

Num- 
ber 

Capa- 
city 

Quantity 

Value 

per 
Gallon 

1° 

111 

Gallons 

Gallons 

Cents 

M  Cu.  Ft. 

Gallons 

Oklahoma.... 

167 

234 

492,436 

115,123,424 

21,541,905 

18.71 

84,719,941 

1.359 

West  Virginia. 

128 

188 

135,663 

32,668,647 

6,511,813 

19.93 

167,771,351 

0.195 

California  

45 

49 

99,761 

28,817,604 

4,438,022 

15.40  ' 

45,351,247 

0.635 

Pennsylvania  . 

287 

251 

59,164 

13,826,250 

2,778,098 

20.01 

49,487,056 

0.279 

Texas  

10 

11 

32,550 

6,920,405 

1,149,441 

16.61 

12,677,216 

0.546 

Ohio  

49 

61 

25,137 

5,439,560 

1,051,376 

19.33 

30,062,141 

0.181 

Louisiana  .... 

15 

20 

20,118 

4,979,754 

814,747 

16.36 

2,233,511 

2.229 

Illinois  

33 

55 

17,392 

4,934,009 

866,033 

17.55 

2,685,895 

1.837 

Kentucky.... 

5 

5 

13,400 

3,818,209 

763,186 

19.99 

24,915,946 

0.153 

Kansas  

4 

6 

4,642 

1,174,980 

241,219 

20.53 

9,315,339 

0.126 

New  York.... 

\ 

Colorado  

/     7 

6 

2,122 

181,262 

33,116 

18.27 

68,154 

2.659 

750 

886 

902,385 

217,884,104 

40,188,956 

18.45 

429,287,797 

0.508 

«U.  S.  Geol.  Survey  Mineral  Resources,  1917,  part  2,  p.  1119, 1919. 


CHAPTER  VII 
ORIGIN  OF  PETROLEUM  AND  NATURAL  GAS 

The  theories  of  the  origin  of  petroleum  and  inflammable  natural 
gas  are  separated  into  two  groups,  which  may  be  called  the  in- 
organic and  the  organic. 

INORGANIC  THEORIES 

The  theory  that  oil  has  been  formed  by  inorganic  processes  has, 
in  one  form  or  another,  been  advocated  by  many  chemists.  Their 
theses  assume  that  waters  or  gases  within  the  earth,  acting  on 
chemical  compounds,  generate  the  hydrocarbons  which  accumulate 
near  the  surface  at  favorable  places.  This  theory  is  attractive 
because  it  suggests  processes  by  which  oil  may  be  continuously 
forming,  the  supplies  being  replenished  in  part  as  they  are  used. 
Notwithstanding  its  attractiveness  the  theory  of  inorganic  origin 
has  not  been  accepted  by  many  geologists  because  of  the  insu- 
perable difficulties  which  it  encounters  in  the  field.  Petroleum 
reservoirs  are  generally  tightly  sealed.  The  rocks  that  have  been 
nearest  the  interior  of  the  earth,  the  igneous  rocks  and  crystalline 
schists,  are  nearly  everywhere  barren  of  oil.  The  geologic  settings 
of  accumulations  of  petroleum  offer  the  extreme  antithesis  to  those 
of  deposits  of  metals  other  than  iron,  which  in  the  main  are  found 
near  the  centers  of  volcanism. 

Berthelot1  showed  that  carbon  dioxide  at  high  temperatures  can 
react  on  free  alkaline  metals,  which  some  have  supposed  the 
interior  of  the  earth  contains,  and  can  yield  acetylene,  which 
would  break  down,  forming  higher  hydrocarbons.  He  showed  that 
n  cetylene  heated  to  high  temperatures  yields  benzene. 

Mendelief 2  suggested  that  iron  carbides  are  present  in  the  inte- 
rior of  the  earth,  and  that  underground  water  coming  into  contact 
with  these  compounds  yields  hydrocarbons.  This  theory  was  sup- 

^ERTHELOT,  P.  E.  M.  I  Sur  POrigine  des  Carbures  et  des  Combustibles 
Mme"raux.  Compt.  Rend.,  vol.  62,  pp.  949-951,  1866. 

2MENDELiEF,  D. :  Enstehung  und  Vorkommen  des  Mineralols.  Abstract 
by  G.  Wagner.  Deutsch.  Chem.  Gesell.  Ber.,  vol.  10,  p.  229,  1877. 

80 


ORIGIN  OF  PETROLEUM  AND  NATURAL  GAS      81 

ported  by  Moissan1  and  others,  who  produced  hydrocarbons  from 
iron  carbides. 

These  and  other  inorganic  theories  have  been  advanced.  Becker2 
attempted  to  show  a  relation  between  areas  of  magnetic  deflection 
due  to  the  presence  of  iron  carbides  and  oil  fields.  The  improba- 
bility of  his  hypothesis  has  been  pointed  out  by  Tarr.3  Coste4  has 
defended  the  inorganic  theory,  but  most  of  his  assumptions  are 
unsubstantiated. 

Nitrogen  is  found  in  many  samples  of  natural  gas  and  petroleum. 
Nitrogen  exists  also  in  some  mines  that  exploit  deposits  of  the 
metals  that  have  been  formed  in  comparatively  late  geologic  time 
and  that  are  associated  generically  with  igneous  rocks.5  It  has 
been  suggested  that  nitrogen  found  in  natural  gas  is  of  deep- 
seated  origin.  This  element,  however,  is  widely  distributed  in 
nature  and  takes  part  in  many  biochemical  processes.  Mabery6 
found  that  samples  of  petroleum  collected  from  widely  separated 
regions  all  contained  nitrogen  compounds.  It  is  present  as  pyri- 
dine  and  quinoline  bases  and  their  derivatives,  and  Mabery  states 
that  the  association  and  composition  of  these  substances  are  such 
that  they  could  have  originated  only  in  plant  and  animal  remains. 

Inspection  of  Mabery's  analyses  with  respect  to  the  depth  of  the 
oil  pools  from  which  the  samples  came,  shows  the  noteworthy  fact 
that  the  deepest  oils  do  not  contain  the  most  nitrogen,  nor  are  those 
found  nearest  the  surface  much  lower  in  nitrogen  than  those  that 
are  found  in  the  deeper  measures.  The  Paleozoic  oils,  which  have 
probably  been  more  deeply  buried  than  those  of  later  age,  do  not 
contain  as  much  nitrogen  as  the  Cretaceous  and  Tertiary  oils.  Of 
the  oils  Mabery  analyzed,  13  are  from  Paleozoic  and  8  from  Ter- 
tiary and  Cretaceous  fields.  The  average  nitrogen  content  of  the 

MOISSAN,  H.:  Sur  la  Formation  des  Carbures  d'Hydrogene  Gazeux  et 
Liquides  par  1' Action  de  1'eau  sur  les  Carbures  M6talliques.  Compt.  Rend., 
vol.  122,  pp.  1462-1467,  1896. 

2BECKER,  G.  F. :  Relations  Between  Local  Magnetic  Disturbances  and  the 
Genesis  of  Petroleum.  U.  S.  Geol.  Survey  Bull  401,  pp.  1-24,  1909. 

STARR,  W.  A. :  The  Lack  of  Association  of  the  Irregularities  of  the  Lines  of 
Magnetic  Declination  and  the  Petroleum  Fields.  Econ.  Geology,  vol.  7, 
pp.  647-661,  1912. 

4CosTE,  EUGENE:  The  Volcanic  Origin  of  Oil.  Am.  Inst.  Min.  Eng.  Trans., 
vol.  35,  pp.  288-297,  1905. 

*EMMONS,  W.  H.:  The  Principles  of  Economic  Geology.     P.  285,  1918. 

MABERY,  C.  F.:  The  Genesis  of  Petroleum  as  Revealed  by  Its  Nitrogen 
Constituents.  Am.  Chem.  Soc,  Jour.,  vol,  41,  No,  10,  pp.  1690-1697,  1919. 


82 


GEOLOGY  OF  PETROLEUM 


Paleozoic  oils  is  0.061  per  cent;  that  of  the  later  oils,  0.104  per  cent. 
These  relations  suggest  that  nitrogen  compounds  in  petroleum 
break  up  with  age,  the  nitrogen  accumulating  in  gas  associated 
with  the  petroleum. 

NITROGEN  CONTENT  OP  OILS* 
PALEOZOIC  OILS 


No. 

Locality 

Rock  Strata 

Depth, 
Feet 

Nitrogen, 
per  Cent 

1 

Dudley,  Ohio  

Berea  grit 

1,400 

0  027 

2 
3 

Emlenton,  Pennsylvania. 
Malta,  Ohio  

Rosenberg  sand 
First  Cow  Run  sand 

1,240 
38 

0.0136 
0  039 

4 

Corning,  Ohio  .  .  . 

Berea  grit 

1  150 

0  410 

5 

Marietta,  Ohio  

Goose  Run  sand 

150 

0.016 

6 

Newport,  Ohio 

Berea  grit 

1,170 

0  024 

7 

Cabin  Creek,  West  Vir- 
ginia 

Berea  grit 

2,700 

0  029 

8 
9 
11 

Titusville,  Pennsylvania 
Emlenton,  Pennsylvania. 
Bartlesville,  Oklahoma 

Third  sand 
Third  sand 

1,200 
1,080 

b0.014 
0.0115 
0.074 

13 
14 

Mahoning  Valley,  Ohio.  . 
Mecca,  Ohio         .    .    . 

Pure  quartz  sand 
Sand 

150 
150 

0.049 
0.054 

20 

Morris,  Kansas 

1,125 

0  035 

TERTIARY   AND   CRETACEOUS   OILS 


10 

Humble  field,  Texas,  me- 
dium   

Sand 

2,750 

0.058 

12 

Vinton,  Louisiana 

2,750 

0  067 

15 

Sour  Lake,  Texas  

Sand 

1,300 

0.067 

16 

Beaumont  Texas 

Sand 

1,000 

0  023 

17 
18 
19 
21 

Jennings,  Louisiana  
Caddo,  Louisiana  
Humble  field,  Texas,  light. 
Baku  Russia 

Sand 
Sand 

Sand 

2,000 
2,200 
950-1,300 

0.480 
0.050 
0.015 
0.071 

aMABEKT,  C.  F.,  op  cit.,  p.  1693.  I  have  taken  the  liberty  to  rearrange  Mabery's  table. — 
W.H.E. 

&  Average  of  two  determinations. 

In  some  gases  from  the  oil  fields  of  the  Mid-Continent  region 
helium1  is  present  with  methane  and  nitrogen.  Its  presence  has 

^ADY,  H.  P.  and  MCFARLANE,  D.  F. :  Chemical  Composition  of  Gas.  Kan- 
sas Geol.  Survey,  vol.  9,  pp.  228-302,  1908. 


ORIGIN  OF  PETROLEUM  AND  NATURAL  GAS      83 

suggested  to  some  investigators  a  deep-seated  source  of  the  gas  and 
the  oil  associated  with  it.  Little  is  known  of  the  geologic  occur- 
rences of  helium.  The  high  molecular  velocity  of  this  light  element 
renders  plausible  the  hypothesis  that  it  departs  from  the  planet, 
and  if  so  it  was  once  more  abundant  in  the  earth  than  it  is  today. 

ORGANIC  THEORIES 

The  theory  that  petroleum  is  generated  by  natural  distillation 
under  geothermal  and  dynamic  influences  from  organic  matter 
buried  in  sediments  was  first  suggested  by  Newberry1  and  by 
Orton.2  Laboratory  experiments  that  support  this  theory  include 
those  of  Warren  and  Storer,3  who  prepared  a  calcium  soap  from 
menhaden  oil  which  on  distillation  yielded  a  mixture  of  hydro- 
carbons like  kerosene.  Engler4  distilled  directly  from  menhaden 
oil  the  paraffins  from  pentane  to  nonane.  Day5  obtained  by  dis- 
tilling a  mixture  of  fresh  herring  and  pine  wood  a  product  that 
yielded  on  redistillation  a  residue  like  gilsonite,  and  by  distilling 
herring  alone  he  obtained  one  like  elaterite. 

Clarke6  mentions  calculations  made  by  Szajnocha  which  show 
that  the  annual  catch  of  herring  on  the  northeast  coast  of  Germany 
could  yield  in  2,560  years  as  much  oil  as  Galicia  has  produced. 

Engler7  obtained  hydrocarbons  by  the  distillation  of  vegetable 
oils.  The  theory  that  oil  is  derived  principally  from  animal 
remains  was  supported  by  Engler8  and  by  Hoefer9,  both  well  known 
for  their  investigations  of  the  origin  of  petroleum. 

DEWBERRY,  J.  S.:  Devonian  System.  Ohio  Geol.  Survey,  vol.  1,  p.  160, 
1873. 

ZORTON,  EDWARD:  The  Origin  and  Accumulation  of  Petroleum  and  Natural 
<2as.  Ohio  Geol.  Survey,  vol.  6,  p.  74,  1888. 

3WARREN,  C.  M.,  and  STORER,  F.  H. :  Examination  of  a  Hydrocarbon  Naph- 
tha Obtained  from  the  Products  of  the  Destructive  Distillation  of  Lime  Soap. 
Acad.  Arts  and  Sci.  Mem.,  2d  ser.,  vol.  9,  p.  177,  1867. 

ANGLER,  C. :  Zur  Bildung  des  Erdols.  Deutsch.  Chem.  Gesell.  Ber.,  vol. 
21,  p.  1816,  1918. 

6DAY,  W.  C. :  The  Laboratory  Production  of  Asphalts  from  Animal  and 
Vegetable  Materials.  Am.  Chem.  Jour.,  vol.  21,  pp.  478-199,  1899. 

CLARKE,  F.  W. :  The  Data  of  Geochemistry,  3d  ed.  U.  S.  Geol.  Survey 
Bull.  616,  p.  730,  1916.  (The  original  paper  is  not  accessible  to  me.) 

ANGLER,  C. :  Cong.  Internat.  du  Petrole,  Paris,  1900,  p.  20. 

SENGLER,  C.:  Zur  Geschicte  des  Bildung  des  Erdols.  Deutsch.  Chem. 
Gesell.  Ber.,  vol.  33,  pp.  7-21,  1900. 

'HoEFER,  H.:  Das  Erdol,  p.  219,  1906. 


84  GEOLOGY  OF  PETROLEUM 

A/IP. 

These  experiments  show  that  compounds  like  those  found  in 
petroleum  may  be  derived  from  either  animal  or  vegetable  matter. 

A  theory  that  is  accepted  by  many  investigators  today  is  that 
there  are  two  stages1  in  the  formation  of  petroleum  from  organic 
material.  In  one  biochemical  processes  predominate;  in  the  other 
geochemical  or  dynamochemical  processes.  Petroleum  is  believed 
to  be  derived  from  remains  of  plants,  especially  from  those  of  low 
orders  yielding  waxy,  fatty,  gelatinous,  or  resinous  substances, 
and  from  animal  matter.  The  organic  matter  was  deposited  on 
the  sea  bottom  in  estuaries  or  not  far  from  shore  and  in  lakes. 
Through  the  action  of  anaerobic  bacteria  it  is  changed,  the  cellu- 
lose probably  being  altered  to  other  compounds  and  the  waxes  and 
fats  set  free.  That  plants  of  low  orders,  when  distilled,  can  yield 
petroleum  was  demonstrated  by  Renault.2  Prominence  is  given 
to  such  plants  in  the  contributions  by  Dalton,  White,  and  Win- 
chester, mentioned  elsewhere. 

The  probability  that  bacterial  action  plays  a  part  in  the  reaction 
that  yields  petroleum  was  brought  forward  by  Morrey.3  That 
the  source  of  the  material  is  principally  muds  and  shales  is  evident 
from  the  association  of  shales  and  clays  with  oil-bearing  strata. 
t  The  anaerobic  bacteria  are  active  probably  as  soon  as  the  mud 
containing  organic  material  is  deposited.  Any  oily  matter  which 
they  set  free  could  accumulate  even  on  the  sea  bottom,  for  fine 
particles  of  clay  surround  globules  of  oil  and  sink  them4  or  hold 
them  below  water.  Oil  will  not  float  long  on  water  that  is  even 
slightly  turbid.  That  is  often  shown  on  the  Mississippi  River 
near  the  Hennepin  Avenue  Bridge  at  Union  Station,  Minneapolis. 
Frequently  oil  is  passed  into  the  river  from  industrial  operations. 
It  covers  the  water  for  a  few  hundred  feet  along  the  river  below  the 


,  W.  H.:  On  the  Origin  of  Petroleum.  Econ.  Geology,  vol.  4, 
pp.  603-631,  1909. 

WHITE,  DAVID:  Some  Relations  in  Origin  Between  Coal  and  Petroleum. 
Washington  Acad.  Sci.  Jour.,  vol.  5,  pp.  189-212,  1915.  Late  Theories  Re- 
garding the  Origin  of  Oil.  Geol.  Soc.  America  Bull.,  vol.  28,  pp.  727-734, 
1917. 

RENAULT,  B. :  Houille  et  Bacteriaces.  Soc.  Hist.  Nat.  Autun.  Bidl.t  vol. 
9,  pp.  475-500,  1896;  Compt.  Rend.,  vol.  117,  p.  593,  1893. 

3MoRREY,  C.  B.,  and  ORTON,  EDWARD:  Origin  of  Oil  and  Gas.  Ohio  Geol. 
Survey  Bull.  1,  p.  313,  1903. 

STUART,  MURRAY:  The  Sedimentary  Deposition  of  Oil.  India  Geol,  Survey 
Rec.,  vol.  40,  pp.  320-333,  1910. 


ORIGIN  OF  PETROLEUM  AND  NATURAL  GAS      85 

bridge  and  disappears  downstream.  After  they  have  sunk  the  oil 
the  clay  particles  can  hold  it  down  permanently,  and  it  will  accu- 
mulate at  the  bottom  of  the  water. 

There  are  few  data  showing  the  depth  at  which  bacterial  action 
takes  place  in  buried  sediments.  Sulphur  bacteria,  which  break 
up  sulphates,  probably  live  very  near  the  sea  bottom.  Murray 
and  Irvine1  show  that  sea  water  associated  with  the  muds  from 
the  sea  bottom  contain  less  than  half  as  much  sulphate  radicle  as 
normal  sea  water.  Shaw2  states  that  anaerobic  bacteria  have  been 
reported  to  be  present  at  depths  of  20  feet  in  bogs. 

Some  processes  that  either  generate  oil  from  the  strata  or  accu- 
mulate it  are  active  for  a  long  time  'after  the  burial  of  the  deposits. 
This  conclusion  is  warranted  by  the  fact  that  oil  accumulates  under 
pressure  in  reservoirs  on  monoclines  that  have  been  sealed  long 
after  burial,  either  by  faults,  by  dikes,  or  by  later  impermeable 
strata  that  are  deposited  above  them  unconformably.  The  oil 
that  had  formed  before  the  top  of  the  reservoir  became  sealed 
would  have  been  expelled  if  it  had  been  under  water  pressure  or 
gas  pressure  at  that  time. 

The  anaerobic  bacteria  that  are  supposed  to  effect  the  decompo- 
sition of  cellulose  in  buried  strata  presumably  work  best  in  the 
presence  of  salt  water.  This  is  suggested  by  the  fact  that  practi- 
cally all  productive  petroleum  deposits  are  found  in  marine  strata 
or  in  beds  closely  associated  with  marine  strata.  Coal  deposits, 
on  the  other  hand,  are  formed  principally  in  fresh  water,  and  the 
beds  most  closely  associated  with  them  are  in  the  main  nonmarine. 

The  sulphur  bacillus  (Bacillus  sulphurens)  and  the  petroleum 
bacillus  (Micrococcus  petroli)  probably  work  together.  Both  are 
anaerobic.  Sea  water  that  has  been  buried  is  depleted  of  sulphates 
(p.  51),  and  some  of  it  carries  hydrogen  sulphide.  Native  sulphur 
is  often  found  in  marine  strata.  Sulphur  bacteria  take  oxygen 
from  sulphates  and  set  sulphur  free. 

Sulphur,  or  its  compounds,  is  found  in  the  petroleum  of  most 
fields,  although  in  some  fields  it  is  present  in  very  small  amounts. 
It  is  abundant  in  the  oils  of  the  Lima-Indiana  field,  where  it  occurs 
as  methyl  sulphide  (CH3)2S.  Other  sulphides  of  the  paraffin 

MURRAY,  J.,  and  IRVINE,  R. :  On  the  Chemical  Changes  in  the  Composition 
of  Sea  Water.  Roy.  Soc.  Edin.  Trans.,  vol.  37,  pp.  481-57,  1895. 

'SHAW,  E.  W. :  The  Role  and  Fate  of  Connate  Water  in  Oil  and  Gas  Sands 
(discussion).  Am.  Inst.  Min.  Eng.  Trans.,  vol.  51,  p.  606,  1915 


86  GEOLOGY  OF  PETROLEUM 

series  have  been  identified.1  Sulphur  compounds  have  been  iden- 
tified in  Canadian  oils,  and  free  sulphur  occurs  in  a  Texas  oil.  The 
sulphur  in  oils  is  probably  derived  from  bodies  of  plants  and  ani- 
mals, many  of  which  contain  sulphur,  as  well  as  from  sea  water. 

Because  practically  all  important  accumulations  of  oil  are  in  or 
near  marine  strata  it  is  supposed  that  organic  matter  buried  in  the 
sea  may  be  more  readily  converted  into  oil  than  organic  matter 
buried  in  fresh  water.  Nevertheless,  oil  shales  such  as  are  sup- 
posed to  have  supplied  some  of  the  materials  for  the  generation  of 
petroleum  are  not  all  marine.  The  Green  River  oil  shales  contain 
remains  of  fresh-water  shells.2  Winchester  suggests  as  probable 
the  hypothesis  that  these  shales  were  the  sources  of  the  great  bitu- 
men dikes  and  asphaltic  sandstones  that  are  present  in  rocks  below 
and  above  them  in  the  Uinta  Basin. 

In  California  several  of  the  formations  associated  with  the  oil 
measures  are  diatomaceous.  One  of  these  formations,  the  Mon- 
terey shale,  is  made  up  almost  entirely  of  diatom  tests.  It  is  more 
than  2,000  feet  thick  and  is  present  in  nearly  every  important  field. 
The  oil  has  accumulated  in  sandstones  associated  with  the  shale. 
As  shown  by  Arnold3  and  his  associates,  the  sandy  members  are 
generally  barren  except  where  diatomaceous  shales  are  present. 

Diatoms  are  free-moving  vegetable  organisms.  They  dwell  in 
the  sea  and  also  in  fresh  waters.  The  larger  number  of  species  are 
marine.  These  live  near  the  sea  bottom  and  on  free-floating 
plants,  in  the  main  of  the  plankton.  Diatoms  have  siliceous  tests 
made  of  two  valves  that  fit  together  as  a  pill-box  fits  into  its  cover. 
They  contain  protoplasm  much  like  that  found  in  other  algal  cells, 
with  chlorophyl,  colored  brown  by  diatomin.  Their  abund- 
ance, the  composition  stated,  and  their  constant  association  with 

JMABERY,  C.  F.,  and  SMITH,  A.  W. :  Sulphur  Compounds  in  Ohio  Petroleum. 
Am.  Chem.  Jour.,  vol.  13,  pp.  233-243,  1891. 

"WINCHESTER,  D.  E.:  Oil  Shale  of  the  Uinta  Basin,  Northeastern  Utah. 
U.  S.  Geol.  Survey  Bull.  691,  pp.  26-50,  1919.  Schuchert  states  that  some 
of  the  shale  deposits  may  be  of  saline  lakes.  Amer.  Inst.  Min.  Eng.  Bull. 
155,  p.  3060, 1919. 

PROF.  CHAS.  SCHUCHERT  suggests  that  the  lake  in  which  the  Green  River 
was  deposited  may  have  been  salt  at  one  time.  Written  communication. 

ARNOLD,  RALPH,  and  ANDERSON,  ROBERT:  Geology  and  Oil  Deposits  of 
the  Coalinga  District,  California.  U.  S.  Geol.  Survev  Bull.  398,  1910. 

ARNOLD,  RALPH,  and  JOHNSON,  H.  R. :  Preliminary^-eport  on  the  McKit- 
trick  Oil  Region.  U.  S.  Geol.  Survey  Bull.  406,  1910. 


ORIGIN  OF  PETROLEUM  AND  NATURAL  GAS      87 

oil-bearing  strata  in  California  have  led  Arnold  to  regard  the  dia 
toms  as  the  principal  sources  of  California  oil  and  gas. 

It  has  been  suggested  that  "kerogen,"  the  oil-yielding  substance 
of  oil  shale  is  the  product  resulting  from  bacterial  action  on  organic 
matter.1  This  substance  is  assumed  by  some  to  represent  a  com- 
mon intermediate  product,  which  may  later,  by  dynamic  meta- 
morphism,  be  transformed  to  oil  and  gas. 

Practically  every  body  of  oil-bearing  strata  in  the  world  includes 
a  considerable  thickness  of  shales  or  clays,  or  of  marls  and  clays. 
These  rocks  not  only  furnish  the  impermeable  covers  necessary  to 
prevent  the  escape  of  oil  or  gas,  but  in  general  they  supply  the 
organic  matter  from  which  the  oil  and  gas  are  derived.  As  a  rule 
the  oil  and  gas  are  found  in  sands  or  sandstones  associated  with 
shales  or  clays,  or  in  fractured  limestones  or  dolomites.  In  a  great 
many  districts  the  producing  strata  consist  of  great  thicknesses  of 
shales  or  clays,  containing  several  relatively  thin  beds  of  sand. 
Such  a  body  of  strata  is  commonly  formed  near  shore,  under  delta 
conditions,  or  offshore  in  water  only  moderately  deep.  Deep-sea 
conditions  are  presumably  less  favorable  for  the  deposition  of  such 
beds.  Twenhofel  states  that  black  hydrocarbonaceous  shale  may 
form  in  water  so  shallow  that  it  is  but  a  step  to  land  conditions. 
In  Esthonia,  on  the  Baltic,  there  are  a  number  of  localities  along 
the  shores  in  which  deposits  of  black  shale  are  now  forming. 2 

It  is  characteristic  of  a  great  many  petroliferous  regions  that  the 
strata  change  within  short  distances  both  laterally  and  vertically. 
Such  changes  are  noteworthy  in  the  oil  fields  of  Burma,  in  the 
Apsheron  region  of  the  Caucasus,  Russia,  in  the  Appalachian  oil 
fields,  in  Oklahoma,  in  California,  and  elsewhere.  In  some  of  the 
Burma  fields  one  well  section  may  differ  greatly  from  that  of  a  well 
a  few  rods  away.  Such  abrupt  changes  in  sediments  are  character- 
istic of  near-shore  conditions.  In  other  fields,  like  those  of 
Indiana,  the  strata  are  persistent,  and  sections  of  wells  started  at 
the  same  geologic  horizon  will  resemble  each  other  closely.  All 
these  data  indicate  that  oil-bearing  sediments  form  most  abun- 
dantly in  shallow  water  and  to  a  less  extent  in  deep  water  though 
not  at  abyssal  depths. 

'STEUART,  D.  R. :  The  Chemistry  of  Oil  Shale;  The  Oil  Shales  of  the  Loth- 
ians.  2d  ed.,  part  3,  p.  164,  Scotland  Geol.  Survey  Mem.,  1912. 

TWENHOFEL,  W.  H:  Notes  on  Black  Shale  in  the  Making.  Am.  Jour.  Sri., 
4th  ser.,  vol.  40,  pp.  272-280,  1915. 


88  GEOLOGY  OF  PETROLEUM 

While  practically  all  of  the  petroliferous  deposits  of  the  world 
are  associated  with  marine  strata,  it  is  possible  that  some  have 
formed  in  saline  lakes.  Schuchert  states  that  "kerogen"  may  be 
formed  in  saline  lakes,  probably  in  those  only  that  are  not  over 
4  per  cent  salt.1 

ASSOCIATION  OF  PETROLIFEROUS  STRATA  AND  COAL 

It  has  been  suggested2  that  oil  is  derived  from  the  materials  that 
form  coal.  "Coal  oil"  and  kerosene  distilled  from  petroleum  are 
nearly  related  with  respect  to  their  physical  properties.  Pictet 
and  Bouvier  distilled  from  a  coal  from  Montrambert,  Loire,  a  tar 
in  which  they  found  CK^O  and  CnH22,  hydrocarbons  identical 
with  some  separated  from  petroleums. 

Coal  has  been  formed  in  the  main  from  vegetable  matter  depos- 
ited in  fresh  water.  If  vegetable  matter  deposited  in  fresh  water 
can  yield  oil,  a  close  association  of  coal  deposits  and  of  oil  deposits 
would  be  expected.  Methane  gas  is  commonly  associated  with 
coals,  and  it  is  reasonable  to  suppose  that  heavier  hydrocarbons 
also  might  be  derived  from  coal-forming  materials.  They  are 
formed  when  coke  is  made  from  coal.  If  there  is  a  close  generic 
relation  between  the  formation  of  coals  and  the  formation  of  oils, 
one  should  expect  frequently  to  find  oil-soaked  coals  and  coal 
measures  impregnated  with  oil,  and  also  coal  or  lignite  in  the  oil 
measures.  The  great  coal-producing  strata  of  the  earth  generally 
are  not  the  oil-producing  strata.  Many  of  the  oil-producing  strata 
are  nevertheless  lignitic  or  closely  associated  with  highly  lignitic 
beds — more  generally  in  Europe  and  Asia  than  in  North  America. 

The  oil-bearing  series  of  Alsace,  near  Schwabweiler,  passes  into 
thin  upper  Oligocene  sandstones,  which  alternate  with  coal  seams 
20  inches  thick  or  less.3  Carbonized  plant  remains  are  found  in 
petroliferous  saliferous  sandstones  in  the  Oligocene  of  the  Bory- 

^CHUCHERT,  CHARLES  :  Petroliferous  Provinces.  Discussion  of  a  paper  by 
E.  G.  WOODRUFF.  Am.  Inst.  Min.  Eng.  Bull.,  155,  pp.  3059-3060,  1919. 

2CuNNiNGHAM-CRAiG,  E.  H. :  Origin  of  Oil  and  Shale.  Royal  Soc.  Edin- 
burgh Proc.,  vol.  36,  pp.  44-86,  1916. 

PICTET,  A.  and  BOUVIER,  M.:  Ueber  die  Distillation  der  Steinkohle  Unter 
Vermindertem  Druck.  Deutsch.  Chem.  GeselL  Ber.,  1913,  pp.  33-42. 

3 VON  WERVEKE,  L. :  Die  Entstehung  der  Unterelsaessischen  Erdoelager 
erlautert  an  der  Schichtenfolge  im  Oligocaen.  Phil.  Gesell.  Elsass-Lothringen, 
Mitt.,  Band  4,  Heft  5,  pp.  697-721,  1913. 


ORIGIN  OF  PETROLEUM  AND  NATURAL  GAS      89 

slaw  field  of  Galicia,1  and  also  in  the  upper  Inoceramus  (Creta- 
ceous) petroliferous  beds  of  the  Schodnica  field.  In  Rumania,  beds 
of  lignite  are  found  in  the  Pontian  (Pliocene)  in  which  petroleum 
also  is  present,  possibly,  however,  as  a  result  of  infiltration  from 
lower  beds.  The  Burdigalian  (Miocene)  petroliferous  sandstones 
of  Rumania  carry  also  beds  of  lignite.  Coal  fragments  occur  in  the 
Pegu  (Miocene)  beds,  which  yield  oil  in  the  principal  fields  of 
Burma.2  Some  of  the  coal  beds  of  Sumatra  are  petroliferous. 

At  Roma,  Queensland,  Australia,  gas  occurs  in  Jura-Trias  rocks 
consisting  of  sandstones,  shales,  and  thin  coal  seams.3  Plant 
remains  are  found  in  the  petroliferous  rocks  of  Trinidad.4 

In  North  America  oil,  coal,  and  lignite  are  geologically  not  so 
closely  spaced,  although  many  of  the  great  oil  fields  are  not  far  from 
the  great  fields  of  coal  and  lignite.  The  coal  fields  of  the  Appa- 
lachian region  are  mainly  within  the  area  bearing  oil,  but  the 
principal  oil-producing  beds  are  below  the  coal-producing  beds 
and  separated  from  them  by  hundreds  of  feet  of  shales.  The 
Ordovician  and  Devonian  oils  of  Ohio,  Indiana,  Kentucky,  Michi- 
gan, and  Ontario  are  not  closely  associated  with  coals.  The  coal 
basin  of  Michigan  lies  above  the  Devonian  strata.  The  coal 
measures  of  the  Michigan  coal  basin  possibly  joined  those  of  the 
Appalachian  coal  basin  before  the  country  was  denuded  by  erosion. 
This,  however,  is  uncertain.  The  Ohio-Indiana  oil  region  was 
once  probably  overlain  by  coal. 

In  Illinois  much  oil  is  found  in  the  coal  series,  but  generally  at 
geologic  horizons  below  those  of  the  coal.  In  the  northeastern 
Oklahoma  oil  fields  coal  beds  are  found  in  the  Pennsylvanian  oil 
measures  associated  with  the  oil  sands.  In  the  Pawhuska  quad- 
rangle, as  noted  by  Heald,5  the  upper  Pennsylvanian  rocks  con- 
tain layers  with  marine  fossils  but  are  accompanied  by  some 
thin  lenticular  beds  of  coal  and  beds  of  clean,  fine-grained  swamp 
clays  with  plant  remains  that  indicate  swamp  or  land  condi- 

1ZuBER,  RUDOLF:  Die  Geologischen  Verhaltnisse  von  Boryslaw  in  Ostga- 
lizien.  Zeitschr.  Prakt.  Geologic,  1904,  pp.  41-48. 

2PASCOE,  E.  H.:  The  Oil  Fields  of  Burma.  India  Geol.  Survey  Mem.,  vol. 
40,  p.  234,  1912. 

SCAMERON,  W.  E. :  Report  on  the  Significance  of  a  Flow  of  Gas  in  the  Roma 
No.  2  Bore.  Queensland  Geol.  Survey  Pub.,  247,  1915. 

CUNNINGHAM-CRAIG,  E.  H. :  Oil  Finding,  p.  13,  London,  1914. 

6HEALD,  K.  C. :  Geologic  Structure  of  the  Northwestern  Part  of  the  Paw- 
huska Quadrangle,  Oklahoma.  U.  S..Geol.  Survey  Bull  691,  p.  61, 1919. 


90  GEOLOGY  OF  PETROLEUM 

tions.  Ripple  marks,  worm  trails,  mud  cracks,  and  footprints 
of  quadrupeds  in  some  of  the  sandstones  show  that  the  materials 
forming  the  beds  were  laid  down  on  tidal  flats,  flood  plains,  or  other 
low  places  where  they  were  not  submerged  at  all  times  or  where 
the  water  was  very  shallow.  Some  of  the  oil  sands  of  northern 
Texas  are  in  coal-bearing  formations.  In  northern  Louisiana  oil 
sands  are  associated  with  lignitiferous  strata.  In  Wyoming  the 
principal  oil  measures  are  older  than  the  Laramie  coal-bearing 
formation  and  younger  than  the  Dakota,  which  in  places  carries 
plant  remains.  In  California  there  are  no  coal  measures  compar- 
able to.  the  oil  measures.  It  is  improbable  that  lignite  has  con- 
tributed any  considerable  portion  of  the  materials  from  which  the 
California  oils  were  derived. 

In  brief,  the  organic  materials  that  have  formed  coals  and  lig- 
nites may  have  contributed  fractions  that  have  accumulated  as 
deposits  of  petroleum  and  gas.  It  is  improbable,  however,  that 
the  principal  coal  deposits  have  formed  from  the  materials  that 
have  contributed  the  principal  petroleum  deposits.  This  is  shown 
at  many  places  by  the  presence  of  barren  sands  between  the  oil 
sands  and  coal  beds.  There  are  probably  in  all  fields,  moreover, 
other  sources  of  organic  matter  adequate  to  have  supplied 
petroleum. 

ACCUMULATION  OF  PETROLEUM  IN  BEDS  FORMED  UNDER  ARID 

CONDITIONS 

Many  .petroliferous  strata  are  closely  associated  with  red  beds, 
salt,  and  gypsum — strata  that  are  assumed  to  have  formed  under 
arid  conditions.  This  association  is  noteworthy,  for  arid  condi- 
tions generally  are  not  favorable  to  the  accumulation  of  organic 
remains.  Salt  and  gypsum  in  the  main  are  formed  in  arms  of  the 
sea  or  precipitated  in  closed  basins,  such  as  do  not  exist  in  moist 
climates.  Most  marine  organisms,  moreover,  will  perish  in  salt 
solutions  that  are  highly  concentrated. 

Not  all  red  beds  are  associated  with  salt  and  gypsum.  Red 
beds  alone  are  not  proof  that  the  conditions  were  arid  when  they 
were  formed.  Many  of  the  deserts  of  today  are  not  conspicuously 
red.  On  the  other  hand,  red  beds  are  now  being  deposited  as 
sediments  at  some  places  in  moist  regions.1 

The  red  shales  that  are  closely  associated  with  many  oil-bearing 

^OMLINSON,  C.  W. :  The  Origin  of  Red  Beds.  Jour.  Geology,  vol.  24,  pp. 
238-253,  1916. 


ORIGIN  OF  PETROLEUM  AND  NATURAL  GAS      91 

series  may  have  become  red  in  part  after  the  shales  were  deposited. 
Red  oxide  of  iron  may  be  formed  from  hydrated  iron  oxide  by  the 
dehydrating  action  of  salt  solutions,1  just  as  anhydrite  is  formed 
from  gypsum.  This  action  may  be  brought  about  in  a  saturated 
solution  of  sodium  chloride  at  a  temperature  not  above  150°  C. 
Concentrated  salt  solutions  are  common  in  oil  fields.2 

The  association  of  oil  deposits  in  many  regions  with  beds  formed 
under  arid  conditions  is  probably  due  in  part  to  the  porosity  of 
sands  formed  under  such  conditions.  In  arid  climates  weathering 
is  largely  mechanical  rather  than  chemical.  The  sands  are  likely 
to  be  clean  and  free  from  clay  particles.  Moreover,  the  wind- 
blown sands  are  commonly  porous,  because  the  wind  sorts  the 
quartz  grains  and  clay  particles.  A  desert  sand,  with  round  grains, 
free  from  clay,  submerged  and  covered  by  marine  organic  clays, 
marls,  or  muds  would  afford  an  excellent  reservoir  for  the  accumu- 
lation of  oil. 

In  the  Appalachian  region  red  sediments  are  closely  associated 
with  many  of  the  oil  and  gas  bearing  beds.  The  Catskill  series 
contains  a  considerable  amount  of  red  shale.  Red  shales  of  the 
Mauch  Chunk  inclose  petroliferous  beds.  In  places  the  " Clinton" 
sand  of  Ohio  is  red.  In  Illinois  red  shales  are  found  in  the  Chester 
(Mississippian),  which  is  oil  bearing.  In  the  Mid-Continent  oil 
field  red  shales  are  associated  with  some  of  the  productive  sands. 
In  the  Appalachian  region  salt  and  gypsum  are  found  in  the 
Salina,  which,  however,  is  not  intimately  associated  with  the  strata 
that  yield  the  petroleum. 

In  some  fields  in  Europe  the  petroliferous  beds  are  associated 
closely  with  land  sediments  formed  under  arid  conditions.  In 
Alsace  the  petroliferous  series  consists  in  part  of  red  marl,  anhy- 
drite, gypsum,  and  pyrite  lenses.  In  some  parts  of  the  district 
coal  seams  are  present.  As  stated  by  Von  Werveke,  the  series  is 
part  marine  and  part  non-marine.  The  conditions  when  it  was 
laid  down  changed  from  marine  to  non-marine,  terrestrial,  and  arid. 
Although  the  oil-bearing  beds  are  associated  with  the  arid  land 
sediments,  where  anhydrite  is  present  there  is  no  oil  in  the  sands. 

^AUBREE,  A. :  Etudes  et  Experiences  Synthetiques  sur  le  Metamorphisme. 
Annales  des  Mines,  5th  ser.,  voL  16,  p.  411,  1859;  Smithsonian  Inst.  Annual 
RepL,  1861,  p.  270. 

2MiLLS,  R.  V.  A.,  and  WELLS,  R.  C. :  The  Evaporation  and  Concentration 
of  Waters  Associated  with  Petroleum  and  Natural  Gas.  U.  S.  Geol.  Survey 
Bull.  693,  p.  24,  1919. 


92  GEOLOGY  OF  PETROLEUM 

In  Galicia  the  Sarmatian  strata  (Miocene)  consist  of  limestone, 
sandstone,  sands,  clays,  and  shales,  with  gypsiferous  and  saliferous 
clays  in  the  lower  part  of  the  section.  The  Sarmatian  Salifere  is 
the  oil-bearing  series  in  the  Boryslaw-Tustanowice  field.  In 
Rumania  gypsum  is  found  in  the  Tortonian  and  Helvetian  of  the 
Miocene.  Both  of  these  formations  carry  petroleum.  The  Sar- 
matian also  carries  petroleum  in  Rumania  and  is  one  of  the  petro- 
liferous series  of  the  Baku  fields,  Russia,  where  it  is  gypsiferous. 

In  Egypt,  Miocene  strata  yield  oil  along  the  west  coast  of  the 
Gulf  of  Suez.  As  stated  by  Hume,  the  oil-bearing  strata  are  asso- 
ciated with  great  thicknesses  of  salt  and  gypsum  beds. 

In  the  Yenangyaung  and  Yenangyat-Singu  fields,  Burma,  the 
oil-bearing  series  is  the  Pegu  formation,  of  Miocene  age,  which  is 
associated  with  red  beds. 

These  associations  are  significant,  yet  practically  all  the  oil-bear- 
ing series  that  contain  beds  formed  under  arid  conditions  include 
also,  associated  with  red  beds,  or  with  red  beds,  salt,  and  gypsum, 
bodies  of  marine  strata  containing  organic  matter  or  remains  of 
organic  bodies,  adequate  to  supply  material  for  the  formation  of 
petroleum.  Strata  formed  under  arid  conditions  doubtless  supply 
the  favorable  reservoirs  rather  than  the  sources  of  organic  matter 
that  yields  petroleum. 

TEMPERATURES  OF  OIL  FIELDS 

Temperatures  increase  with  depths  in  the  earth,  in  general  at 
the  rate  of  about  1°  F.  for  60  or  70  feet.  Many  observations  have 
been  made  in  mines  and  wells,  and  the  results  differ  widely  owing 
to  differences  in  local  conditions,  such  as  ventilation  in  mines,  the 
structure  of  the  rocks,  and  the  nearness  to  watercourses  of  points 
where  observations  have  been  taken.  Temperatures  are  higher 
in  some  oil  fields  than  elsewhere  at  similar  depths.  Koenigsberger 
and  Muehlberg1  have  suggested  that  temperature  gradients  may 
be  used  in  prospecting  for  oil.  The  differences  in  the  gradients 
of  oil  fields  are  so  great,  however,  that  the  value  of  their  conclusions 
is  somewhat  problematic.  Nevertheless,  so  far  as  is  indicated  by 

KOENIGSBERGER,  JOH.  :  Normale  und  anormale  Werte  der  Geothermischen 
Tiefenstufe.  Centralbl.  Mineralogie  Jahrbuch,  1905,  pp.  673-679. 

KOENIGSBERGER,  JOH.  and  MUHLBERG,  MAX:  On  the  Measurements  of  the 
Increase  of  Temperature  in  Bore  Holes.  Inst.  Min.  Eng.  (England)  Trans., 
vol.  39,  pp.  617-644, 1910;  Ueber  Messungen  der  Geothermischen  Tiefenstufe. 
Neues  Jahrb.,  Beilage  Band  31,  pp.  107-157,  1911. 


ORIGIN  OF  PETROLEUM  AND  NATURAL  GAS      93 

data  now  available,  the  temperatures  in  oil  fields  are  generally 
above  normal.  Rogers1  has  recently  investigated  this  problem 
and  has  found  a  high  gradient  in  the  Sunset-Midway  district, 
California. 

Many  factors  affect  the  accuracy  of  observations  of  temperatures 
in  borings  and  of  fluids  that  are  encountered  in  them.  Expanding 
gases  cool  the  fluids,  and  temperatures  change  somewhat  as  the 
fluids  rise.  These  factors  are  discussed  by  Rogers. 2  So  far  as  is 
indicated  by  data  now  available,  temperatures  generally  increase 
more  rapidly  in  Cretaceous  and  Tertiary  oil  fields  than  they  do  in 
older  ones.  That  is  not  true  everywhere,  however,  for  the  gradient 
in  certain  Rumanian  fields,  where  the  oils  are  found  only  in  Ter- 
tiary strata,  are  lower  than  in  the  Bartlesville  field,  Oklahoma, 
where  oil  is  derived  from  Pennsylvanian  strata.  The  data  avail- 
able are  not  sufficient  for  generalization,  although  they  indicate 
an  attractive  problem  for  study. 

There  is  little  exact  data  indicating  the  temperatures  that 
formerly  existed  in  oil  fields.  Some  of  the  Sunset-Midway  oils  of 
California  are  over  120°  F.  and,  according  to  Pack,3were  probably 
hotter  at  times  of  migration. 

Willis4  states  that  the  lowest  strata  of  the  Appalachian  geo- 
syncline  when  deeply  buried  probably  had  a  temperature  of 
about  200°  C. 

^ROGERS,  G.  S. :  The  Sunset-Midway  Oil  Field,  California,  part  2.  U.  S. 
Geol.  Survey  Prof.  Paper  117,  pp.  37-42,  1919. 

20p.  tit.,  pp.  42-43. 

3PACK,  R.  W. :  The  Sunset-Midway  Oil  Field,  California.  U.  S.  Geol.  Sur- 
vey Prof.  Paper  116,  p.  74,  1920. 

4WiLLis,  BAILEY:  Geologic  Distillation  of  Petroleum.  Bull.  Amer.  Inst. 
Min.  Eng.  No.  157.  sec.  10,  pp.  1-7,  1920. 


94  GEOLOGY  OF  PETROLEUM 

GEOTHERMAL  GRADIENT  IN  OIL  FIELDS  AND  IN  OTHER  REGIONS" 


Depth 
of 
Well 

Tempera- 
ture at 
Bottom 

Depth  per 
Degree  of 
Increase  in 
Tempera- 
ture 

Remarks 

Observer 

Oil  fields: 

Feet 

Deg.  F. 

Feet 

Sunset-Midway,     Cali- 

fornia 

1,470- 

97-131 

41.0 

Based  on  average  of  corrected 

Rogers 

3,870 

temperature  of  water  in  9 

- 

wells  in   western   part   of 

field 

Bartlesville,  Oklahoma. 

1,275 

84 

51.0 

Oil  well 

Woodruff6 

Batson,  Texas 

1,100 

101 

34.5 

Oil  and  water  well 

Fcnncmjin  c 

Florence,  Colorado  .... 

44.0 

Based  on  average  tempera- 

Washburne'* 

ture   of   oil  produced    by 

many  wells 

Findlay,  Ohio 

3,000 

82.1 

95.8 

Precise  measurements 

Johnston  * 

Wheeling,    West    Vir- 

ginia  . 

4,462 

110.15 

75.2 

Precise  measurements  in  dry 

Hallock' 

hole 

Vera  Cruz,  Mexico  .... 

2,276 

122.9 

48.6 

Furbero  oil  field 

Miihlberg* 

Pechelbronn,  Alsace  .  .  . 

1,692 

25.3-38.3 

Asphaltic  shale  oil 

Branca  * 

Campina,  Rumania..  .  . 

2,726 

99.3 

54.7 

Dry  hole 

Tanasescu* 

Lucacesti-Zemes,     Ru- 

mania   

1,575 

70.7 

69.8 

Oil  and  water  well 

Tanasescu* 

Bibi-Eibat,     Apsheron 

Peninsula,  Russia  .  .  . 

2,695 

114.5 

47.7 

Thermometer  submerged  for 

Goloubjatni- 

11  hours  in  oil  well 

kov» 

Samarinda,  Borneo.  .  .  . 

2,214 

51.0 

Oil  well  producing  light  par- 

Mtthlberg* 

affin  oil 

Echigo,  Japan  

2,381 

118.6 

39.2 

Kawamura* 

Other  districts: 

Bay  City,  Michigan  .  .  . 

3,455 

97.0 

68.5 

Lane* 

Charleston,  South  Car- 

olina   

2,001 

99.7 

57.5 

Temperature    of    outflowing 

Knappm 

water 

Ames,  Iowa  

2,100 

63.4 

129.  6.' 

Precise  measurements 

Beyerw 

Maris,  Holland  

4,265 

138 

50.5 

Precise  measurements 

Beyer" 

Schladebach,  Germany. 

5,630 

133.9 

67.2 

Precise  measurements 

Dunkerp 

Paruschowitz,  Ger- 

many   

6,427 

156.7 

62.1 

Precise  measurements 

Henrich* 

"ROGERS,  G.  S. :  The  Sunset-Midway  Oil  Field,  California,  part  2.  U.  S.  Geol.  Survey  Prof. 
Paper  117,  p.  41,  1919. 

6Personally  communicated  by  N.  H.  DARTON. 

TENNEMAN,  N.  M.:  Oil  Fields  of  the  Texas-Louisiana  Gulf  Coastal  Plain.  U.  S.  Geol. 
Survey  Bull.  282,  p.  56,  1906. 

dWABHBXJRNE,  C.  W.:  The  Florence  Oil  Field,  Colorado.  U.  S.  Geol.  Survey  Bull.  381, 
p.  530,  1910. 

*JOHNSTON,  JOHN,  and  ADAMS,  L.  H. :  On  the  Measurement  of  Temperatures  in  Bore  Holes. 
Econ.  Geology,  vol.  11,  p.  741,  1916. 

'HALLOCK,  WILLIAM:  Deep  Well  at  Wheeling,  West  Virginia.  Am.  Jour.  Set.,  3d  ser.,  vol.  43, 
pp.  234-236,  1892;  School  of  Mine  Quart.,  vol.  18,  pp.  148-153,  1897. 


ORIGIN  OF  PETROLEUM  AND  NATURAL  GAS      95 

'KoNiGSBERGER,  J.,  and  MUHLBERQ,  M.:  On  Measurements  of  the  Increase  of  Temperature 
in  Bore  Holes..  Inst.  Min.  Eng.  (England)  Trans.,  vol.  39,  pp.  617-644,  1910 

^BRANCA,  W.;  Ver.  Naturkunde  in  Wiirttemberg  Jahreshefte,  1897,  p.  42. 

'TANASESCU,  I.:  Etudes  Preliminaries  sur  le  Regime  Thermique.  Inst.  Geol.  Romanei 
Annarul,  vol.  5,  iasc.  la,  p.  Ill,  1912. 

'GoLOUBJATNiKOV,  D.:  Observations  Geothermiques  a  Bibi-Eibat  et  Sourakhany  (in  Rus- 
sian). Com.  Geol.  Mem.,  nouv.  ser.,  livr.  141,  p.  32,  1916.  The  observation  cited  is  close  to 
the  average  of  several  hundred  careful  measurements.  The  average  gradient  in  the  neighbor- 
ing Sourakhany  field  is  44.5. 

*KAWAMURA:  On  the  Geothermic  Gradient  in  the  Echigo  Oil  Fields,  Japan  (in  Japanese). 
Geol.  Soc.  TokioJour.,  vol.  19,  pp.  179-185,  222-227,  1912. 

'LANE,  A.  C.:  The  Geothermal  Gradient  in  Michigan.  Am.  Jour.  Set.,  4th  ser.,  vol.  9, 
p.  435,  1900. 

OTSTEPHENSON,  L.  W. :  A  Deep  Well  at  Charleston,  South  Carolina.  U.  S.  Geol.  Survey 
Prof.  Paper  90,  p.  70,  1915. 

"BEYER,  S.  W.:  Iowa  Agricultural  College  Water  Supply,  pp.  13-14,  Ames,  1897. 

°Temperatur-Metingen  in  Diepe  Boorgaten.  Ryksopsporing  van  Delfstoffen  Jaarveralag, 
1912,  pp.  27-28. 

PDUNKER,  E. :  Ueber  die  Temperatur-Beobachtungen  im  Bohrloche  zu  Schladebach.  Neues 
Jahrb.,  1889,  Band  1,  pp.  29-47. 

«HENRICH,  F.:  Ueber  die  Temperaturverhaltnisse  in  dem  Bohrloch  Paruschowitz  V.  Zeit- 
tchr.  prakt.  Geologie.  vol.  12,  pp.  316-320,  1904. 


CHAPTER  VIII 

MAPS  AND  LOGS 
STRUCTURAL  CONTOUR  MAPS 

Structural  contour  maps  are  used  extensively  in  mapping  oil 
fields.  They  show  approximately,  by  contours,  the  position  of  a 
bed  or  horizon  over  the  entire  area  mapped,  and  one  familiar  with 
their  use  may  picture  the  structure  from  them  at  a  glance.  As  a 
rule  it  is  not  possible  to  map  a  bed  or  horizon  over  a  large  folded 
area.  At  some  places  it  may  be  removed  by  erosion ;  at  others  it 
may  be  concealed.  Its  outcrops  are  mapped  and  their  elevations 
noted  at  many  places,  with  the  dip  and  strike  (Fig.  14).  Its  posi- 


FIG.  14. — Sketches  showing  parts  of  folds.   (After  Willis.) 


tions  in  wells  are  also  recorded.  Where  it  has  been  removed  by 
erosion  any  bed  below  it  that  is  now  exposed  is  noted,  and  the 
former  position  of  the  bed  to  be  mapped  is  estimated  from  its 
distance  above  the  exposed  bed  in  the  geologic  column  as  deter- 
mined within  or  near  the  area. 

If  the  structure  is  domatic  the  contours  will  "close,"  or  pass  all 
the  way  around  the  dome.     Such  a  fold  is  called  a  "closed  fold." 

96 


MAPS  AND  LOGS 


97 


FIG.  15. — Sketch  map  showing  elevation  of  the  same  stratum  at  diff3rent 
points,  marked  by  crosses.   (After  Gardner.) 


FIG.  16. — Sketch  map  showing  elevations  of  same  stratum  at  different  points 
marked  by  crosses  as  in  Fig.  15.  The  structure  contours  are  drawn  connecting 
points  of  equal  elevation,  thus  outlining  an  elongated  dome.  (After  Gardner.) 


17.— Lengthwise  section  of  elongated  dome  shown  in  Fig.  16,  vertical 
scale  greatly  exaggerated.   (After  Gardner.) 


98 


GEOLOGY  OF  PETROLEUM 


Fig.  15  is  a  sketch  showing  elevations  of  the  same  stratum  or 
horizon  at  different  places.     Fig.  16  is  a  sketch  of  the  same  area 


FIG.  18. — Cross  section  and  sketch  of  an  anticline  illustrating  the  use  of 
structure  contours  (above.)  Structure  contour  map  of  the  same  anticline  is 
shown  below.  The  structure  contours  are  drawn  on  the  top  of  sandstone  X  Y  Z. 
(After  Hewett  and  Lupton.) 


MAPS  AND  LOGS 


99 


with  structural  contours  drawn  to  connect  points  of  equal  eleva- 
tion. It  outlines  an  elongated  dome,  or  anticline,  with  at  least  30 
feet  of  closure.  Fig.  17  is  a  lengthwise  section  of  the  anticline, 
in  which  the  vertical  scale  is  greatly  exaggerated. 


Line  of  outcrop- letter 

desigria  ting  bed 

.  ^ —  ^ ^71  • 

\f~~         I    Line  of  outcrop  inferred 


/600J    Contour  line 
'  s  ,'1600?  \    Contour  inferred 
_...''\    ;.-•']     Dim  road  or  trail 
Rooid  or  highway 
X         I    Read  station  on  bed 
5?         I    Plane  table  station 


Triangulcition  station 

Red  turning  point  on  bed 

Length  of  shot  and  percent  or  dip 

Section  corner  found 

Error  of  closure 

Line,  of  traverse  (not  side  shot;,) 


fault  visible 

Fault  concealed  or  inferred 

Company  headings 


NOTE 'Make  the  following  symbol  &j^  in  diameter^  regardless  of  scale  of  map 

O  Well. location  <J>  Temporarily  abandoned,  well  casing 

©  Derrick  up  not  pulled 

O  Drilling  well  ^  Combination  oil  and  gas  well 

•  OH  well  X  Oil  seep  at  surface 

&  Gas  weft  9  Oil  showing  in  drilled  well 

-<>-  Pry  hole  abandoned  *  Gas,  showing  at  surface 

+  Abondoned  well.  £.  Gas  showing  in  drilled  well 

Y  Abandoned  gas  well  • 


Columnar  sections  must  show  brief  description 
of  beds  and  depth  to  oil  sands 


FIG.  19. — Symbols  commonly  used  on  field  maps.  (After  Woodruff.) 

In  ordinary  mapping  of  beds  having  complicated  structure  it  is 
not  regarded  good  practice  to  use  a  vertical  scale  on  the  cross  sec- 
tion that  is  different  from  the  horizontal  scale,  because  it  gives  a 


100 


GEOLOGY  OF  PETROLEUM 


distorted  picture  of  the  structure.  For  mapping  flat-lying  rocks, 
however,  this  practice  is  necessary.  In  some  fields  the  folds  are 
so  low  that  they  can  not  be  shown  on  a  true  scale.  If  a  contour 
map  is  used  to  depict  the  structure,  together  with  the  section,  the 
amount  of  exaggeration  is  instantly  apparent. 

In  some  fields  the  relation  of  oil  and  gas  accumulations  to  struc- 
ture is  very  close.  On  the  presence  of  a  closure  of  30  feet  may 
depend  the  localization  of  30  feet  of  sand  saturated  with  oil  or  gas. 


30?       40°        50°      60°       70°       60°      90" 
Angle  Between  Direction  of  Dip  and  Direction  of  Dip  Component 

FIG.  20. — Chart  for  determining  the  amount  of  true  dip,  when  components 
are  known,  on  lines  oblique  to  line  of  dip.  Horizontal  lines  represent  true  dip, 
curved  lines  represent  dip  components.  (After  Lahee.} 

The  mapping  is  done  as  accurately  as  is  possible,  with  instruments 
of  precision. 

Small  domes  like  that  shown  in  Fig.  16  are  typically  developed 
in  the  oil  fields  of  Oklahoma  and  Kansas.  In  fields  in  mountain- 
ous countries  the  structural  features  are  larger  and  the  dips 
steeper.  Fig.  18  shows  a  sketch  and  cross  section  of  an  anti- 
cline, with  a  contour  map. 

It  is  desirable  that  as  far  as  practicable  the  same  symbols  be 


MAPS  AND  LOGS  101 

used  on  different  maps.  Fig.  19  is  a  chart  prepared  by  E.  G. 
Woodruff,  showing  symbols  that  are  commonly  used. 

When  the  true  direction  of  dip  of  a  bed  and  the  differences  in 
elevations  of  the  bed  in  different  wells  are  known,  it  is  frequently 
desirable  to  determine  the  amount  of  dip.  Fig.  20  is  a  chart 
prepared  by  F.  H.  Lahee  for  this  purpose.  Suppose  two  well  logs 
show  a  difference  in  elevation  of  a  certain  bed  amounting  to  30  feet 
to  a  mile  in  a  direction  N.  40°  E.  The  true  dip  is  known  to  be 
N.  80°  E.  The  angle  between  the  true  dip  and  the  dip  component 
is  40°.  The  intersection  of  the  vertical  line  marked  "40°"  with  the 
curve  marked  "30"'  indicates  that  the  amount  of  the  true  dip 
between  the  two  wells  is  about  40  feet  to  the  mile. 

In  many  fields,  formations  above  the  oil-bearing  strata  have  the 
forms  of  flat-lying  wedges,  or  are  tabular  bodies  thicker  at  some 
places  than  at  others,  varying  irregularly.  To  show  these  varia- 
tions the  convergence  sheet  is  used.  Such  sheets  are  frequently 
made  on  transparent  paper  or  cloth  and  placed  above  the  map. 
The  depth  of  the  oil  sand  may  then  be  readily  estimated  where  the 
out-cropping  horizons  and  elevation  are  accurately  plotted.  In 
the  Appalachian  region  the  Devonian  rocks  increase  gradually  from 
Ohio  eastward.  The  rate  of  increase  is  shown  by  the  parallel  lines 
in  Fig.  101,  after  I.  C.  White.  These  lines  show  the  convergence 
of  the  strata  from  east  to  west.  The  convergence  sheet  is  used  in 
drawing  structural  contours  on  the  key  bed,  or  on  the  oil-bearing 

stratum. 

WELL  LOGS 

Well  logs  are  utilized  when  they  are  accessible.  In  fields  covered 
with  mantle  rock  these  supply  most  of  the  detailed  information. 
Some  companies  provide  for  samples  to  be  taken,  at  regular  inter- 
vals, from  the  holes,  but  as  a  rule  the  written  well  records  only  are 
accessible.  That  is  particularly  true  in  the  United  States  where 
most  fields  are  developed  by  two  or  more  companies,  and  where, 
generally,  there  is  a  courteous  interchange  of  such  data.  The 
driller's  log  depends  principally  upon  the  erudition  of  the  driller 
and  his  previous  experience.  He  often  carries  the  names  of  rocks 
encountered  in  one  district  to  another  perhaps  far  removed,  and  in 
different  surroundings.  The  rocks  encountered  with  the  cable  or 
impact  drill  may  be  recorded  differently  when  encountered  with 
the  rotary  drill  which  progresses  by  abrasion. 

A  "hard  rock"  is  generally  one  that  is  hard  to  make  progress  in. 


102         .GEOLQGY  OF  PETROLEUM 

If  the  cable  system  is  used,  a  stratum  of  gypsum  might  be  classed 
as  a  hard  rock  because  it  is  elastic  and  not  readily  broken  by  blows, 
whereas  a  hard,  brittle  limestone  which  is  easily  drilled  would  be 
classed  as  "soft."  The  gypsum  would  be  classed  as  soft  if  the  rotary 
system  is  used,  because  it  is  readily  cut,  whereas  the  limestone 
which  resists  abrasion  would  be  hard. l 

"Slates"  are  reported  in  most  logs  of  wells  that  are  driven  through 
argillaceous  rocks  that  are  more  consolidated  than  clays  or  soft 
shales.  Oil  sands  are  rocks  that  contain  oil,  whether  sands,  sand- 
stones)  limestones,  or  dolomites. 

With  the  rotary  drill,  a  formation  is  "sticky"  which  cuts  in  large 
pieces  that  adhere  to  the  bit  and  drill  pipe.  A  formation  that  is 
sticky  with  the  rotary  is  usually  sticky  with  the  cable  tools.  On 
the  other  hand,  formations  are  encountered  in  which  the  cable  tools 
stick,  owing  either  to  the  elasticity  of  the  formation  or  to  the  fact 
that  the  drill  ed-up  particles  do  not  mix  readily  with  the  water  in 
the  hole  and  settle  so  quickly  as  to  stick  the  bit.  These  formations 
might  not  appear  sticky  to  the  rotary  driller. 

The  term  "sandy"  may  be  used  accurately  by  the  cable-tool 
driller.  He  obtains  samples  of  the  formation  through  which  he 
passes,  of  sufficient  size  to  determine  the  relative  amount  of  sand 
to  clay  or  sand  to  shale  in  any  formation.  In  the  case  of  the  rotary 
drill,  this  term  is  misleading.  The  rotary  well  is  drilled  with  the  aid 
of  a  "mud"  of  varying  density.  It  is  usually  a  mixture  of  clay,  sand, 
and  water.  It  often  contains  as  high  as  40  to  50  per  cent  sand. 
As  stated  by  Knapp,  any  change  in  the  density  of  the  mud  changes 
its  capacity  to  carry  sand.  Even  a  small  shower  falling  on  the 
slush  pit  will  change  the  density  enough  to  cause  some  of  the  sus- 
pended sand  to  be  precipitated.  These  properties  of  the  mud  lead 
to  error  in  the  observation  of  the  formation.  If  a  clay  formation 
containing  a  moderate  amount  of  sand  is  encountered  while  drilling 
in  a  mud  low  in  sand  content,  the  mud  will  absorb  most  of  the 
sand,  which  will  not  settle  out  in  the  overflow  ditch  and  its  presence 
in  the  formation  will  not  be  noted,  if  not  felt  by  the  action  of  the 
bit  in  drilling.  If,  some  time  later,  the  mud  is  thinned  by  adding 
water  this  sand  will  appear  in  the  overflow  and  may  be  attributed 
to  a  formation  many  feet  below  the  one  from  which  it  actually 
originated. 

*KNAPP,  A. :  Rock  Classification  from  the  Oil-driller's  Standpoint.  Mining 
and  Metallurgy,  sec.  26,  No.  158,  pp.  1-6,  February,  1920. 


MAPS  AND  LOGS  103 

The  so-called  "jigging"  action  of  the  rising  column  of  mud  on 
the  sand  or  cuttings  also  leads  to  misinterpretation.  The  deeper 
the  drill,  the  finer  the  sand  in  cuttings  brought  to  the  surface  by 
mud.  As  stated  by  Knapp,  the  coarser  particles  are  pounded 
into  the  walls  of  the  well  or  broken. 

A  change  in  the  speed  of  pumping  the  mud  also  causes  a  change 
in  the  amount  and  size  of  the  cuttings  that  appear  at  the  surface. 
Thus,  in  the  case  of  the  rotary,  "sandy"  may  have  little  or  no 
meaning  when  applied  to  a  formation.  The  term  sandy  is  often 
used  in  contradistinction  to  sticky.  A  formation  that  drills  easily 
and  is  not  sticky  is  often  recorded  as  sandy  because  sand  tends 
to  decrease  stickiness. 

A  wet  specimen,  fresh  from  the  hole,  has  a  different  color  from 
the  same  specimen  dried.  Many  specimens,  when  dried,  bleach. 
Many  of  them  air  slack  or  oxidize.  The  terms  light  and  dark 
should  be  used  only  for  the  extremes.  They  are,  in  general, 
relative.  A  sample  of  wet  shale  examined  under  an  electric  light 
might  appear  darker  than  in  daylight.  The  terms  indicating 
shades  are  more  definite  than  light  and  dark,  and  are  recommended 
by  Knapp. 

Clay  is  readily  recognized  by  the  "feel  of  the  bit"  while  drilling 
with  either  cable  tools  or  rotary.  To  some  drillers  all  clay  is 
gumbo  while  to  others  gumbo  is  only  sticky  clay.  Some  clays 
have  the  property  of  cutting  in  large  pieces  but  do  not  adhere 
excessively  to  the  bit  and  drill  pipe  and  are  designated  as  "tough." 

Free,  uncemented  sand  is  easily  recognized  by  the  feel  of  the 
tools  in  both  systems  of  drilling.  "Packed  sand"  is  a  sand  that  is 
slightly  cemented  with  some  soft,  easily-broken  cementing  material, 
such  as  calcium  carbonate.  It  cuts,  when  drilled  with  a  rotary, 
with  much  the  same  feeling  as  when  cutting  crayon  with  a  knife. 
The  cementing  material  is  dissolved  or  broken  before  reaching  the 
surface,  so  that  the  driller  finds  only  sand  in  the  overflow.  A 
microscopic  examination  of  sands  from  the  overflow  often  shows 
cementing  material  to  be  present  when  not  suspected  by  the  action 
of  the  bit. 

A  quicksand  is  one  that  caves  or  sticks  the  tools;  a  heaving  sand 
is  one  that  rises  in  the  bore.  A  "shell"  may  be  the  test  of  an 
organism  or  a  thin  layer  of  any  kind  of  sedimentary  rock. 


104 


GEOLOGY  OF  PETROLEUM 


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CHAPTER  IX 
ACCUMULATION  OF  PETROLEUM 

Water,  oil,  and  gas  in  porous  strata  tend  to  arrange  themselves 
in  accordance  with  their  density — the  oil  above  the  water  and  the 
•gas  above  the  oil  (Fig.  21).  In  folded  rocks  that  are  saturated  with 
water,  oil,  and  gas,  the  oil  and  gas  rise  to  the  crests  of  the  upfolds, 
or  anticlines,  and  the  water  is  found  on  the  flanks  of  the  anticlines 
and  in  synclines.  If  the  rocks  are  dry  the  oil  is  found  low  on  the 
folds  or  in  synclines.  If  some  water  is  present,  the  oil  floats  on 
the  water  and  will  .be  found  low  on  the  anticlines,  its  position 


'Oil  and  Gas 


FIG.  21. — Section  through  Bartlesville  sand,{Cushing  field,  Oklahoma.  (After 

Deal.} 

depending  on  the  amount  of  water  present.     On  monoclines  that 
are  sealed  the  oil  rises  above  the  water,  and  the  gas  above  the  oil. 

THE    ANTICLINAL    THEORY 

The  theory  of  gravitational  arrangement  according  to  density 
is  generally  referred  to  as  the  anticlinal  theory  or  the  structural 
theory.  This  theory  was  formulated  as  a  result  of  work  in  the 
Appalachian  field  of  the  United  States  and  in  the  Ontario  field.  It 
is  doubtful,  however,  whether  the  theory  meets  so  many  difficulties 
in  any  other  large  oil  field  in  the  world,  as  in  the  Appalachian 
region,  where  many  of  the  sands  are  not  saturated  with  water.  In 
these  sands  the  oil  is  found  far  down  on  the  flanks  of  the  anticlines 
and  in  synclines.  At  some  places,  especially  in  the  well-known 
fields  in  Pennsylvania  near  Pittsburgh,  these  sands  are  very  pro- 
ductive, and  it  was  natural  that  the  theory  should  have  met  a  lack 
of  enthusiasm  where  pronounced  exceptions  to  it  were  so  prom- 
inently displayed. 

The  fact  that  oil  and  gas  and  water  will  separate  by  gravity  was 

105 


106  GEOLOGY  OF  PETROLEUM 

first  noted  in  America1  by  Andrews2  and  by  Hunt.3  Andrews  had 
studied  the  Burning  Springs-  Volcano  anticline  of  West  Virginia, 
and  Hunt  the  Petrolia  and  Oil  Springs  domes  of  Lambton  County, 
Ontario.  In  these  localities  the  segregation  of  oil  and  its  accumu- 
lation at  the  tops  of  domes  is  very  marked.  (See  Figs.  13  and  26.) 

Alexander  Winchell  and  J.  S.  Newberry  gave  the  theory  a  more 
definite  form.  Winchell4  based  his  conclusions  chiefly  on  the  rela- 
tions he  had  observed  in  Ontario,  and  Newberry5  on  the  areas  in 
western  Pennsylvania,  West  Virginia,  and  eastern  Ohio.  In  the 
years  immediately  following  these  discussions  the  theory  made 
little  progress.  The  fields  of  Pennsylvania  were  then  being 
developed,  and  in  these  fields  many  of  the  accumulations  are  in 
synclines.  Lesley  6  and  his  associates  of  the  Pennsylvania  Geologi- 
cal Survey  opposed  the  anticlinal  theory.  The  theory  was  dis- 
credited in  many  quarters,  because  so  many  exceptions  to  it  had 
been  found.  I.  C.  White7  revived  it,  worked  out  many  problems 
nearly  related  to  it,  and  was  probably  the  first  investigator  to  use 
it  in  a  practical  way. 

Orton  agreed  with  White  as  to  his  main  contention  and  soon 
after  the  discovery  of  oil  in  the  Trenton  fields  of  Ohio  and  Indiana 
made  a  survey  of  the  fields  and  found  that  accumulations  were 
on  or  near  anticlinal  axes  and  on  terraces,  or  "arrested  anti- 


and  HOEFER  state  that  Oldham  recognized  a  connection  between 
the  anticline  and  oil  accumulation  at  Yenangyaung  in  1855  (Das  Erdoel,  Band 
2,  p.  18). 

ANDREWS,  E.  B.:  Rock  Oil,  Its  Relations  and  Distribution.  Am.  Jour. 
Sci.,  2d  ser.,  vol.  32,  pp.  85-91,  1861. 

3HuNT,  T.  S.  :  Notes  on  the  Geology  of  Petroleum  or  Rock  Oil.  Canadian 
Naturalist,  vol.  6,  pp.  241-255,  1861. 

4WiNCHELL,  ALEXANDER:  On  the  Oil  Formation  in  Michigan  and  Elsewhere. 
Am.  Jour.  Sci.,  2d  ser.,  vol.  39,  p.  352,  1865;  Something  About  Petroleum, 
in  Sketches  of  Creation,  Harper  &  Brother,  1870;  also  notes  in  appendix 
about,  initial  production  of  Ontario  wells. 

DEWBERRY,  J.  S.  :  Devonian  System.  Ohio  Geol.  Survey,  vol.  1,  p.  160, 
1873. 

LESLEY,  J.  P.  :  Geology  of  the  Pittsburgh  Coal  Region.  Am.  Inst.  Min. 
Eng.  Trans.,  vol.  14,  pp.'  654-655,  1886. 

ASHBURNER,  C.  A.  :  The  Production  and  Exhaustion  of  the  Oil  Regions  of 
Pennsylvania  and  New  York.  Am.  Inst.  Min.  Eng.  Trans.,  vol.  14,  pp.  419- 
428,  1886;  The  Geology  of  Natural  Gas.  Idem,  p.  434. 
"  7WniTE,  I.  C.  :  The  Geology  of  Natural  Gas.  Science,  vol.  6,  June  26,  1885; 
Petroleum  and  Natural  Gas.  West  Virginia  Geol.  Survey,  vol.  A,  pp.  48-64, 
1904  (a  reprint  and  amplification  of  the  first  paper). 


ACCUMULATION  OF  PETROLEUM  107 

clines,"  where  there  was  a  flattening  of  the  northward  dip  of 
the  strata.1  Later  Orton  published  a  monograph  on  the  Lima- 
Indiana  field.2  In  this  paper  he  amplified  his  former  discoveries 
and  presented  a  map,3  which  is  probably  the  first  contour  map 
drawn  for  the  purpose  of  showing  structure  in  ail  oil  field.  This 
report  marks  .a  decided  advance  in  geologic  methods  applied  to 
mapping  the  structure  of  oil  fields.  It  was  followed  by  a  series  of 
brilliant  papers  by  men  engaged  in  the  survey  of  the  Appalachian 
oil  region  by  the  United  States  and  Pennsylvania  geological  sur- 
veys, under  the  direction  of  Campbell.  These  reports  and  the 
structural  contour  maps  accompanying  them  have  shown  that  oil 
and  gas  occur  at  the  tops  of  structural  uplifts  in  saturated  rocks 
and  lower  in  unsaturated  rocks.  Woolsey4  in  1906  noted  that  the 
oil  was  found  high  in  anticlines  where  the  beds  contain  water  and 
in  the  hollows  of  synclines  where  they  do  not.  F.  G.  Clapp 5  and 
Stone  and  Clapp 6  investigated  further  the  occurrence  and  relations 
of  oil,  gas,  and  water  in  unsaturated  synclines.  Griswold  and 
Munn7  in  1907  made  a  detailed  report  on  a  large  area  in  south- 
western Pennsylvania  in  which  the  oil  in  the  saturated  rocks,  the 
Big  Injun  sand  and  beds  above  it  was  found  in  the  higher  parts  of 
anticlines,  and  that  in  the  unsaturated  rocks,  the  Squaw  sand  and 
those  below  it,  on  the  flanks  of  anticlines  and  in  synclines.  (See 
Fig.  63.)  They  suggested  the  hypothesis  that  the  unsaturated 
rocks  had  formerly  been  saturated  and  partly  drained.  Later 
Reeves8  reviewed  the  problem  and  noted  that  the  unsaturated 

^RTON,  EDWARD:  The  Origin  and  Accumulation  of  Petroleum  and  Natural 
Gas.  Ohio  Geol.  Survey,, vol.  6,  p.  94,  1888. 

2ORTON,  EDWARD  :  The  Trenton  Limestone  as  a  Source  of  Petroleum  and 
Inflammable  Gas  in  Ohio  and  Indiana.  U.  S.  Geol.  Survey  Eighth  Ann.  Rept., 
part  2,  pp.  475-662,  1889. 

3Idem,  pi.  55,  opp.  p.  548. 

4WooLSEY,  L.  H. :  Economic  Geology  of  the  Beaver  Quadrangle,  Pennsyl- 
vania. U.  S.  Geol.  Survey  Bull.  286,  p.  81,  1906. 

5CLAPP,  F.  G. :  Economic  Geology  of  the  Amity  Quadrangle,  Pennsylvania. 
U.  S.  Geol.  Survey  Bull.  300,  pp.  1-145,  1907. 

6STONE,  R.  W.,  and  CLAPP,  F.  G. :  Oil  and  Gas  of  Greene  County,  Penn- 
sylvania. U.  S.  Geol.  Survey  Bull  304,  pp.  79-82,  1907. 

VGRISWOLD,  W.  T.  and  MUNN,  M.  J. :  Geology  of  the  Steubenville,  Burgetts- 
town,  and  Claysville  Quadrangles,  Ohio,  West  Virginia,  and  Pennsylvania. 
U.  S.  Geol.  Survey  Bull  318,  1907. 

SREEVES,  FRANK:  The  Absence  of  Water  in  Certain  Sandstones  of  Appa- 
lachian Oil  Fields.  Econ.  Geology,  vol.  12,  pp.  354-378,  1917. 


108  GEOLOGY  OF  PETROLEUM 

rocks  in  the  Catskill  of  the  Devonian  are  a  fresh-water  or  terri- 
ginous  series  that  was  probably  dry  when  buried  below  the  sea. 
He  recorded  great  flows  of  salt  water  from  deep  wells  below  the 
Devonian,  opposing  suggestions  made  earlier  that  the  Catskill 
rocks  had  dried  out  after  being  buried. 

During  the  development  of  the  California  oil  fields,  Arnold  and 
his  associates  worked  out  the  structural  details  of  accumulations. 
They  found  that  the  principal  oil  pools  are  on  anticlines  and  mono- 
clines sealed  with  asphalt  or  by  faults.1 

Later  the  structural  relations  in  the  Illinois  fields  were  found  to 
accord  with  the  gravitational  theory.  The  accumulations  of  the 
Kansas,  Oklahoma,  Texas,  Louisiana  and  Wyoming  fields  were 
found  to  be  in  accord  with  it  except  where  the  rocks  are  dry. 
Some  of  the  deposits  are  found  in  sealed  monoclines  or  terraces, 
but  the  gravitational  arrangement2  is  in  general  clearly  expressed. 
Nearly  every  governmental  report  on  an  oil  field  in  any  country 
that  has  been  published  in  recent  years  discusses  the  relations  of 
the  accumulation  to  structure.  These  relations  are  treated  else- 
where (pp.  120-169). 

The  differences  in  the  surface  tension  of  oil  and  water  cause  them 
to  separate,  the  oil  and  gas  occupying  the  large  spaces  and.  the 
water  the  smaller  ones.  This  segregation,  as  pointed  out  by  Wash- 
burne,3  attends  gravitational  separation,  and  its  influence  has  been 
noted  in  many  fields  (p.  112). 

The  theory  of  gravitational  separation  of  gas,  oil,  and  water  is 
demonstrated  in  so  many  fields,  so  widely  separated,  and  under  so 
many  different  conditions  that  additional  proof  is  not  required  to 
substantiate  it.  The  gas  is  above,  and  with  the  oil,  and  generally 
both  are  above  salt  water.  This  arrangement  is  modified  by  capil- 

1  ARNOLD,  RALPH  and  ANDERSON,  ROBERT:  Geology  and  Oil  Resources  of  the 
Coalinga  District,  California.  U.  S.  Geol.  Survey  Bull.  398,  pp.  1-354, 1910. 

ARNOLD,  RALPH  and  JOHNSON,  H.  R. :  Preliminary  Report  on  the  McKitt- 
rick-Sunset  Oil  Region,  Kern  and  San  Luis  Obispo  Counties,  California.  U.  S. 
Geol.  Survey  Bull.  406,  pp.  1-225,  1910. 

ELDRIDGE,  G.  H.,  and  ARNOLD,  RALPH:  The  Santa  Clara  Valley,  Puente 
Hills,  and  Los  Angeles  Districts,  Southern  California.  U.  S.  Geol.  Survey 
Bull.  309,  pp.  1-266,  1907. 

*CLAPP,  F.  G. :  Revision  of  the  Structural  Classification  of  Petroleum  and 
Natural  Gas  Fields.  Geol.  Soc.  America  Bull,  vol.  28,  pp.  553-602,  1916. 

3WASHBURNE,  C.  W. :  The  Capillary  Concentration  of  Gas  and  Oil.  Am. 
Inst.  Min.  Eng.  Bull.  93,  pp.  2365-2378,  1914. 


^ACCUMULATION  OF  PETROLEUM  109 

lary  attraction.  Where  there  are  great  differences  in  the  sizes  of 
the  openings  that  constitute  the  reservoirs,  the  water  clings  tena- 
ciously to  the  smaller  openings,  and  the  larger  ones  are  filled  with 
oil  and  gas.  To  some,  however,  this  theory  appears  inadequate. 
In  many  fields  the  line  between  water  and  oil  is  not  level.  The 
amount  of  oil  that  can  be  removed  from  a  reservoir  is  estimated  to 
be  10  to  75  per  cent1  of  that  originally  contained.  In  some  porous 
sandstones  so  much  oil  remains  that  after  drying  they  contain  from 
4  to  8  per  cent  or  more  of  bitumen.  Originally  the  oil  sands  must 
have  contained  much  less  than  4  per  cent,  for  in  many  fields  the 
expanses  of  the  "dry"  oil  sands  are  at  least  20  times  as  great  as  the 
producing  areas.  The  unproductive  parts  of  the  oil  sands,  more- 
over, are  either  essentially  barren  of  oil  or  contain  much  less  than 
the  parts  that  have  been  drained  by  man.  Evidently  nature's 
process  of  accumulating  an  oil  pool  is  more  efficient  than  man's 
process  of  draining  it. 

Various  theories  have  been  proposed  as  corallaries  to  the  anti- 
clinal theory.  Of  these  the  hydromotive  theory  of  Munn  is  per- 
haps the  best  known. 2  He  suggests  that  bodies  of  water  in  motion 
carry  the  oil  with  them.  If  the  water  moved  downward  or  later- 
ally it  could  carry  the  oil  with  it,  and  the  oil  carried  down  would 
tend  to  float  into  any  higher  structural  features  it  encountered  and 
accumulate  in  them.  The  higher  folds  would  serve  as  oil  traps 
raised  above  the  passageways  of  water  and  oil.  If,  in  depths 
below  the  higher  folds  the  sands  were  for  any  reason  impermeable, 
the  downward  flow  would  turn  to  a  horizontal  course  and  larger 
volumes  of  water  might  pass  below  the  oil  trap,  giving  greater 
opportunities  for  segregation. 

Johnston3  suggests  that  the  oil  is  carried  through  the  sands  as 
films  on  globules  of  gas.  Daly4  appeals  to  pressures  generated 
as  a  result  of  diastrophic  movement.  These  methods  of  segrega- 
tion probably  assist  gravitational  separation  to  some  extent. 

There  is  reason  to  suppose  that  the  temperatures  of  the  oil 

1LEWis,  J.  O. :  Methods  for  Increasing  the  Recovery  from  Oil  Sands.  U.  S. 
Bur.  Mines  Bull.  148,  pp.  25-28,  1917. 

2MuNN,  M.  J. :  The  Anticlinal  and  Hydraulic  Theories  of  Oil  Accumulation. 
Econ.  Geology,  vol.  4,  pp.  509-529,  1909. 

•JOHNSTON,  R.  W. :  The  Accumulation  of  Oil  and  Gas  in  Sandstone.  Science, 
new  ser.,  vol.  35,  pp.  458-459,  1912. 

4DALY,  MARCEL:  Water  Surfaces  in  the  Oil  Fields.  Am.  Inst.  Min.  Eng. 
Trans.,  vol.  59,  pp.  557-563,  1918. 


110 


GEOLOGY  OF  PETROLEUM 


measures  have,  in  general,  been  higher  than  they  are  now.  The 
water  ejected  from  the  Dos  Bocas  well  in  Mexico,  was  hot.  The 
temperatures  of  muds  ejected  from  a  mud  volcano  off  the  coast  of 
Burma  was  148°  F.  In  many  fields1  there  is  reason  to  suppose 
that  temperatures  in  the  oil  sands  have  been  as  high  as  70°  C. 
Oil  loses  viscosity  with  increase  of  temperature  and  would  be  less 
readily  adsorbed  by  grains  of  sand.  At  depths  of  6,000  feet  some 
oils  would  be  no  more  viscous  than  water., /  If  a  vessel  is  filled 
with  sand  that  is  saturated  with  oil,  and  the  bottom  is  perforated 
so  that  all  the  oil  that  can  be  removed  by  gravity  will  drain  out, 


(a)  { 

Glass  tube  bent  to  represent  anticline. 


U) 

Glass  tube  filled  with  oil  sand  and  sea  water,  acidified  with  acetic  acid.  Ground 
dolomite  was  introduced  at  A  and  A'. 


(O 

Same  as  226,  after  48  hours.  AA'  is  dolomite;  BB'  sea  water  in  sand;  CC'  segre- 
gation of  oil  in  sand;  D  accumulation  of  gas  in  sand. 

FIG.  22. — Experiment  illustrating  accumulation  of  oil  and  gas  in  sand. 

much  oil  will  remain  in  the  sand.  If  air  is  blown  through  the  sand, 
more  oil  will  be  removed.  If  water,  hot  water,  and  superheated 
water,  are  successively  passed,  through,  additional  oil  will  be  car- 
ried out  with  each.  The  water  of  oil  fields  is  probably  rarely  as 
hot  as  steam,  but  efficiency  to  overcome  adhesion  is  aided,  doubt- 
less, by  high  temperature.  Oil  will  absorb  more  gas  than  water, 
and  the  gas  makes  it  lighter  and  assists  accumulation.  An  in- 
crease of  temperature  of  only  50°  C.  will  decrease  the  density  of 

iWASHBURNE,  C.  W.  i  The  Role  and  Fate  of  Connate  Water  in  Oil  Sands, 
Am.  Inst.  Min.  Eng.  Trans.,  vol.  51,  p.  607,  1915, 


ACCUMULATION  OF  PETROLEUM  111 

oil  appreciably,  increasing  the  difference  in  weight  between  oil 
and  water. 

A  series  of  experiments  has  recently  been  made  in  the  geological 
department  of  the  University  of  Minnesota,  in  which  gas  was  intro- 
duced into  an  oil-soaked  sand  in  a  closed  system.  Tubes  about 
six  feet  long,  were  bent  to  form  anticlines  of  which  the  limbs  had 
slopes  of  about  15  degrees.  (Fig.  22a.)  These  were  filled  with  sand 
which  had  been  mixed  with  oil.  The  amount  of  oil  introduced  was 
only  that  which  adhered  to  the  sand,  the  excess  having  been 
drained  away.  This  was  charged,  together  with  sea  water  which 
had  been  made  slightly  acid  with  acetic  acid.  The  tube  was  com- 
pletely filled  with  the  mixture  and  allowed  to  remain  a  considerable 
period,  as  shown  by  Fig.  226.  No  segregation  took  place  except 
locally,  where  the  oil  gathered  into  small  drops.  Subsequently 
small  amounts  of  dolomitic  limestone  were  introduced  at  each  end 
of  the  tube  (Fig.  226;  A,  A').  After  forty-eight  hours  a  consider- 
able segregation  of  oil,  gas,  and  water  had  taken  place.  (Fig.  22c). 
The  gas  occupied  the  highest  part  of  the  tube  (D),  and  rested  on 
oil  (C,  C'),  which  in  turn  rested  on  salt  water  (B,  B') l.  The  space 
occupied  by  the  gas  represents  air  spaces  which  it  was  not  possible 
to  eliminate  in  charging  the  water  and  the  oil  soaked  sand  in  the 
tube,  together  with  the  space  made  available  by  the  gas  pressure 
forcing  liquids  into  small  cracks  of  the  sand. 

The  method  of  segregation  is  due  principally  to  gravity.  Grav- 
ity, however,  will  not  operate  in  the  absence  of  gas,  because  adhe- 
sion is  great  enough  to  hold  the  oil  tightly  to  the  sand.  The  gas 
generated  presses  on  both  oil  and  water,  but  the  oil  being  lighter  is 
pushed  up  farther  and  rides  above  the  water.  It  is  clear  that  the 
oil  is  not  carried  by  the  gas  as  films  on  gas  bubbles,  because  the 
amount  of  oil  is  much  greater  than  would  be  required  to  form  films. 
A  small  amount  of  gas  seems  to  be  as  effective  as  a  large  amount, 
provided  the  pressure  is  sufficient.  That  the  pressure  is  effective, 
rather  than  the  movement  of  the  gas,  is  clear  from  additional  exper- 
iments. The  system,  with  acid  and  dolomite,  was  set  up  exactly 
as  is  shown  in  Fig.  22c,  but  the  tube  was  arranged  to  represent 
a  syncline  rather  than  an  anticline.  The  gas  rose  on  either  limb, 
near  the  end  of  the  tube,  the  oil  below  the  gas,  and  water  segre- 
gated below  the  oil.  A  terrace  was  set  up,  the  tube  being  bent  so 

IPTHIEL,  G.  A. :  Gas  an  Important  Factor  in  Oil  Occurrence.  Eng.  and  Min. 
Jour.,  vol.  109,  p.  888,  1920. 


112 


GEOLOGY  OF  PETROLEUM 


that  two  arms  sloped  approximately  15°.  Between  the  two  arms 
the  tube  was  level,  as  it  was  also  at  the  upper  end.  After  being 
charged  with  oil  soaked  sand,  acidified  sea  water  and  dolomite, 
the  oil  rose  to  the  first  level  of  the  terrace  and  remained  several 
days.  Subsequently  it  moved  up  the  higher  inclined  arm  to  the 
flat  portion  of  the  tube.  There  was  a  strong  tendency  for  the 
maximum  accumulation  to  remain  in  the  flat  part  of  the  tube 
nearest  the  bent  limb. 

In  other  experiments  gasoline  or  ether  was  used  instead  of 
acid  and  dolomite.  On  warming  the  system  similar  results  were 
obtained. 

SEGREGATION  OF  OIL  AND  WATER  DUE  TO  DIFFERENCES  IN  THEIR 
SURFACE  TENSION 

Surface  tension  is  the  tension  of  a  liquid  by  virtue  of  which  it 
acts  as  an  elastic  enveloping  membrane,  tending  always  to  con- 
tract to  the  minimum  area. 1  It  is  best  exemplified  in  films  freed 
from  liquid  masses,  as  in  soap  bubbles,  and  in  the  formation  of 
drops.  It  is  commonly  explained  as  due  to  the  fact  that  while 
molecules  in  the  interior  of  the  liquid  are  attracted  in  all  directions, 
and  are  thus  in  equilibrium,  those  on  the  surface  have  no  neighbors 
outside  to  balance  the  attraction  of  those  within  and  are  conse- 
quently acted  upon  by  a  resultant  force  tending  toward  the 
interior.  . 

CAPILLARY  CONSTANTS  OF  THE  PARAFFIN  SERIES" 


Substance 

Tempera- 

Surface 

Substance 

Tempera- 

Surface 

(Nermal) 

ture, 

Tension6 

(Normal) 

ture, 

Tension6 

Deg.  C. 

Deg.  C. 

C5Hiz 

11.0 

16.0 

CuHZ4 

14.0 

26.4 

CeHu 

11.0 

20.0 

ClzH26 

12.8 

27.2 

C7H,6 

12.0 

23.5 

CisHzs 

14.0 

27.9 

C;Hi6 

12.0 

23.4 

Ci«H.i 

13.0 

28.7 

CsHis 

11.0 

24.3 

ClsH32 

13.3 

29.4 

C9H2o 

14.0 

24.9 

CieHsi 

14.0 

29.8 

CioH22 

13.0 

25.8 

"Compiled  by  C.  W.  WASHBURNE. 
6Dynes  per  centimeter. 

^tandarcTDictionary. 


ACCUMULATION  OF  PETROLEUM 


113 


As  a  result  of  surface  tension,  water  and  oil  will  be  drawn  into 
small  openings  of  capillary  size,  regardless  of  the  force  of  gravity. 
Examples  are  the  movements  of  water  into  a  sponge  or  the  rise  of 
oil  in  a  lamp  wick.  The  surface  tension  of  a  water-air  surface  is 
about  75.6  dynes  per  centimeter  at  0°  C.  and  72.8  dynes  at 
20°  C.  Washburne1  states  that  the  surface  tension  of  salt  water 
such  as  is  found  in  oil  fields  is  79  dynes  per  centimeter.  Washburne 
found  also  that  Pennsylvania  crude  oil  (specific  gravity  0.852)  had 
a  tension  of  24  dynes  at  20°  C.2 

As  water  has  about  three  times  the  surface  tension  of  crude  oil, 
capillary  action  must  exert  about  three  times  as  much  pull  upon 


FIG.  23A. — Diagram  illustrating  apparatus  used  in  experiment  to  show  move- 
ment of  oil  from  oil-soaked  mud  to  coarse  sand.  (After  McCoy.) 


FIG.  23B. — View  of  apparatus  illustrated  in  Fig.  23A,  showing  accumulation  of 
oil  in  coarse  sand  after  movement  from  oil-soaked  mud.  (After  McCoy.) 

it.  The  amount  of  the  capillary  pull  varies  inversely  as  the  diam- 
eter of  a  pore.  Hence  the  constant  tendency  of  capillarity  is  to 
draw  water  rather  than  oil  into  the  finest  openings,  displacing  the 
gas  and  oil  in  them.  Gas  can  not  be  drawn  into  capillary  openings 

WASHBURNE,  C.  W. :  The  Capillary  Concentration  of  Gas  and  Oil.  Am. 
Inst.  Min.  Eng.  Trans.,  vol.  50,  pp.  829-842,  1914. 

2The  movements  of  oil  and  water  in  quartz  sand,  due  to  differences  in  surface 
tension,  are  probably  similar  to  movements  in  contact  with  glass.  In  clayey 
containers  the  results  may  be  quantitatively  different,  Exact  data  are  not 
available. 


114 


GEOLOGY  OF  PETROLEUM 


Unprcducuve Weils  .     Oilpooliin  Structure  Contour*  Oil poolsin Third      Oil  pool*  in  Oilpooljm _. 

mhundredfootSond    Hunjrsdfoot  Sand  top  of  H^ndredfoot        Sand  BoulJer  Sand  Sand  Snee 

|M.»"f  o<  thes,  proouce    (with  »lt  water)    Sand.  (Dotum  1000  (No  salt  water).      (No  ioll  water)  Sands 


FIG.  24. — Map  showing  oil  wells  in  Sewickley  quadrangle,  Pennsylvania. 

(After  Munn.) 


by  surface  tension,  hence  water  can  force  it  out  of  the  fine  pores 
without  any  resistance.     Therefore,  as  stated  by  Washburne,1 
gas  is  the  most  quickly  and  completely  gathered  in  the  largest 
I0p.  tit.,  p.  832. 


ACCUMULATION  Of  PETROLEUM 


115 


openings  available.  Capillarity,  moreover, 
of  water  from  fine  to  large  pores 
more  than  it  resists  the  move- 
ment of  oil  and  gas  from  them. 
Thus  water  will  enter  fine  capil- 
laries about  three  times  as  readily 
as  oil,  and  it  encounters  about 
three  times  as  much  capillary  re- 
sistance in  leaving  them.  Conse- 
quently oil  and  gas  are  concen- 
trated in  the  largest  openings,  as 
the  largest  openings  have  the 
least  capillary  power. 

Capillary  action  is  not  exerted 
in  supercapillary  openings.  (See 
p.  41.)  As  water  is  most  readily 
removed  from  such  openings  by 
capillary  action  in  the  surround- 
ing material  they  are  most  readily 
filled  with  oil  and  gas. 

Capillary  attractions  decrease 
with  increase  of  temperature  and 
therefore  with  increase  of  depth. 
With  an  increase  of  1°  C.  per  30 
meters  in  depth,  capillary  action 
loses  half  its  force  at  a  depth  of 
about  5,000  meters.  As  heat  in- 
creases more  rapidly  downward 
in  many  oil  fields  than  the  normal 
increase,  it  is  probable,  according 
to  Washburne,  that  capillary 
force  decreases  one-half  at  depths 
of  3,000  or  4,000  meters.  More- 
over, the  surface  tensions  of  all 
but  the  lightest  hydrocarbons  de- 
crease much  less  rapidly  than  that 
of  water  for  each  increment  of 
temperature,  so  that  the  surface 
tension  of  water  does  not  have 
such  great  excess  over  that  of  oil  at  these 


the  movement 


depths.    Hence  it  is 


116  GEOLOGY  OF  PETROLEUM 

probable  that  the  capillary  concentration  of  oil  and  gas  must  all 
be  effected  within  4,000  or  5,000  meters  of  the  ground  surface. 
Oil  in  deeper  strata  must  remain  diffused  in  the  shales,  if  that 
was  its  original  distribution,  unless  it  was  concentrated  in  the 
sands  at  some  former  period  when  the  strata  concerned  were 
closer  to  the  surface. 

If  oil-soaked  mud  is  placed  near  water-soaked  sand  the  oil  will 
move  to  the  sand.  McCoy1  placed  in  a  glass  box  a  water-soaked 
sand  bed(B,  Fig.  23 A)  in  which  was  a  layer  of  coarser  sand  (A). 
Above  the  sand  was  placed  water-soaked  mud  (C),  containing  a 
layer  of  oil-soaked  mud  (D).  Two  series  of  these  beds  at  different 
levels  were  separated  by  a  celluloid  sheet  (E),  representing  a  fault. 
Within  one  hour  after  removal  of  the  sheet,  oil  began  to  collect  in 
the  layer  of  the  sand  having  the  largest  pores,  and  it  continued  to 
do  so  for  several  hours  until  the  porous  sand  was  nearly  filled  on 
each'side  of  the  plane  representing  the  fault  (Fig.  23B).  Water,  by 
capillary  action,  had  partly  replaced  the  oil  in  the  oil-soaked  mud. 

In  the  Sewickley  quadrangle,  near  Pittsburgh,  Pennsylvania,2 
oil  is  produced  from  the  Catskill  sands  (Devonian)  and  from  the 
Hundred-foot  sand,  near  or  above  the  top  of  the  Devonian.  The 
Hundred-foot  sand  is  from  30  to  125  feet  thick  and  is  saturated 
with  salt  water.  The  sand  is  of  medium  grain  and  porosity  and 
contains  lenses  of  coarse  sandstone  and  conglomerate  which  are 
much  more  porous  than  the  surrounding  sand.  The  porous  lenses 
are  a  mile  long,  more  or  less,  and  a  few  feet  thick.  Practically  all 
the  oil  is  concentrated  in  them.  The  country  is  thrown  into  very 
gentle  folds,  and  nearly  all  the  lenses  or  "pay  streaks"  that  con- 
tain oil  are  in  the  higher  parts  of  the  anticlines.  The  oil  is  asso- 
ciated with  gas  under  pressure  and  with  salt  water.  Down  the  dip 
and  in  synclines  the  pay  streaks  generally  carry  water  only.  Some 
of  the  wells  have  flowed  as  much  as  2,000  barrels  of  oil  a  day.  This 
area  is  shown  in  the  accompanying  map  (Fig.  24).  The  section  in 
Fig.  25  illustrates  the  occurrence  of  oil  on  anticlines  in  the  pay 
streaks.  The  pools  lower  on  the  flanks  of  anticlines  and  in  syn- 
clines in  the  sands  below  the  Hundred-foot  sand  (Fig.  24)  are 
noteworthy. 

^cCoY,  A.  W.:  Notes  on  Principles  of  Oil  Accumulation.  Jour.  Geol, 
vol.  27,  pp.  252-262,  1919. 

8MuNN,  M.  J. :  Studies  in  the  Anticlinal  Theory  of  Oil  and  Gas  Accumula- 
tion.Econ.  Geology,  vol.  4,  pp.  141-157,  1909. 


ACCUMULATION  OF  PETROLEUM  117 

FRACTIONATION  OF  PETROLEUM  IN  CLAY 

Jt  has  been  suggested  that  some  white  oils  and  some  very  light 
oils  have  been  formed  by  the  fractionation  of  petroleum  that  has 
passed  through  clay.  When  oil  is  mixed  with  fuller's  earth  and 
then  displaced  with  water  about  two-thirds  of  the  oil  will  pass  out 
and  one-third  of  the  oil  will  remain  in  the  earth.  As  shown  by 
Day1  and  his  associates,  oil  passing  through  a  dry  fine  clay  (fuller's 
earth)  loses  its  sulphur  compounds,  unsaturated  compounds,  and 
heavier  components  more  readily  than  its  lighter  ones. 

When  petroleum  is  allowed  to  rise  in  a  tube  packed  with  dry 
fuller's  earth,  the  fraction  at  the  top  of  the  tube  is  lighter  than  the 
one  at  the  bottom.  When  water  is  added  to  fuller's  earth  that 
contains  petroleum,  the  oil  which  is  displaced  first  differs  in 
specific  gravity  from  that  which  is  displaced  afterward,  when  more 
water  is  added.  The  paraffin  hydrocarbons  tend  to  collect  in  the 
lightest  fraction  at  the  top  of  the  tube,  and  the  unsaturated  hydro- 
carbons at  the  bottom. 

JDAY,  D.  T.:  Experiments  on  the  Diffusion  of  Crude  Petroleum  Through 
Fuller's  Earth.  Science,  new  ser.,  vol.  17,  pp.  1007-1008,  1903. 

GILPIN,  J.  E.,  and  CRAM,  M.  P.:  The  Fractionation  of  Crude  Petroleum  by 
Capillary  Diffusion.  U.  S.  Geol.  Survey  Bull  365,  pp.  1-33,,  1908. 

GILPIN,  J.  E.,  and  BRANSKY,  O.  E. :  The  Diffusion  of  Crude  Petroleum 
Through  Fuller's  Earth,  with  Notes  on  Its  Geologic  Significance.  U.  S.  Geol. 
Survey  Bull.  475,  pp.  1-50,  1911. 


118 


GEOLOGY  OF  PETROLEUM 


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ACCUMULATION  OF  PETROLEUM 


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CHAPTER    X 

STRUCTURAL  FEATURES  OF  OIL  AND  GAS  RESERVOIRS 
RESERVOIRS  IN  ANTICLINES  AND  DOMES 

Occurrence. — In  accordance  with  the  gravitational  theory  of 
accumulation,  where  reservoir  rocks  are  saturated  with  salt  water, 
oil  will  rise  above  the  water  and  gas  above  the  oil.  On  a  fully 
developed,  regular  structural  dome  the  normal  arrangement  would 
be  a  circular  area  of  gas  wells  surrounded  by  a  belt  of  oil  wells, 
which  in  turn  is  surrounded  by  an  area  containing  salt-water  wells 
only.  This  ideal  arrangement  is  not  the  most  common  one  in  oil 
fields,  because  most  structural  features  are  irregular  in  form,  and 
oil  sands  rarely  have  uniform  porosity.  Gas  and  oil,  moreover, 
in  many  petroleum  fields  occur  together  and  will  issue  simultan- 
eously from  wells  drilled  on  the  tops  of  folds.  In  many  folds  the 
water  is  not  clearly  segregated  from  the  oil.  Many  wells  yield 
mixtures,  some  of  them  emulsions  of  oil  and  water.  Size  of  pores 
also  influences  segregation  (p.  112).  There  is,  nevertheless,  in  al- 
most every  great  oil  field  in  the  world  a  distinct  segregation  of 
oil  and  gas  in  the  higher  parts  of  the  uplifts. 

In  the  Appalachian  oil  field  of  North  America  oil  and  gas  are 
generally  accumulated  in  anticlines  except  in  terrestrial  rocks,  the 
sands  of  which  are  not  saturated  with  water.  The  Venango  group 
of  southwestern  Pennsylvania  is  a  prolific  series  of  dry  or  partly 
dry  sands  in  which  much  of  the  oil  is  found  in  synclines.  In  the 
Carboniferous  strata  above  the  Venango  group  the  oil  is  found  in 
saturated  rocks  and  accumulates  near  the  tops  of  the  anticlines. 
In  the  Volcano  anticline  of  West  Virginia  the  oil  has  accumulated 
near  the  crest  of  a  dome  (Fig.  26).  In  the  Lima-Indiana  field  of 
Ohio  and  Indiana,  where  oil  is  found  in  the  Trenton  limestone,  the 
accumulation  lies  below  or  near  a  broad  anticlinal  axis  that  extends 
northward  from  the  vicinity  of  Cincinnati  and  branches,  one  end 
trending  toward  the  south  end  of  Lake  Michigan,  and  the  other 
toward  the  west  end  of  Lake  Erie.  In  Ohio  the  best  yield  is  ob- 
tained below  the  arch  and  on  terraces ;  in  Indiana  it  is  found  on  the 
north  side  of  the  arch,  where  the  rocks  dip  northeast.  The  east 
branch  of  the  axis  of  the  Cincinnati  anticline  becomes  essentially 

120 


STRUCTURAL  FEATURES  OF  RESERVOIRS       121 


EXPLANATION 

•  Oil  Well 

#  Gas  Well 
+     Dry  Hole 

•>^900 —   Structure    Contour   Lines,     showing  Elevation 
of  Washington    Coal -Bed  above  Tide 

1    H  H  H   0  1 2 3 4 

Scale  of  Miles 


FIG.  26. — Contour  map  of  a  part  of  the  Volcano  anticline,  Wood,  Richie. 
Wirt  and  Pleasants  Counties,  West  Virginia.  Contour  interval  100  feet. 
(After  White,  Grimsley  and  Hennen,  West  Virginia  Geol.  Survey.) 

flat  north  of  Lake  Erie,  in  the  region  of  Lake  St.  Clair.  North  of 
Lake  St.  Clair,  however,  an  axis  may  be  traced  northeastward  to 
the  Petrolia  dome,  in  Lambton' County,  Ontario.  Practically  all 


122 


GEOLOGY  OF  PETROLEUM 


the  oil  produced  in  Canada  has  come  from  Lambton  and  Middle- 
sex Counties,  Ontario,  where  at  Petrolia,  at  Oil  Springs,  and  in 
Mosa  Township  the  oil  has  accumulated  in  well-defined  domes. 


V          X    \      V* 

IPf ;^^°  /"x,..;- -"' }      1 1 


FIG.  27. — Sketch  showing  structure  of  principal  oil  region  of  Lambton  County, 
Ontario.  (After  Williams.} 


In  this  district  a  subordinate  amount  of  oil  has  been  found  also  on 
anticlinal  noses  on  the  flanks  of  the  domes.  (Figs.  27,  28). 


STRUCTURAL  FEATURES  OF  RESERVOIRS      123 


CLASSIFICATION  OF  OIL  AND  GAS  RESERVOIRS 


A.  Elevated  structural  features. 

1.  Anticlines    and    domes:       Appa- 

lachian fields  and  Lima-Indiana 
in  part,  southwestern  Ontario, 
Illinois,  Mid-Continent  field, 
Wyoming,  California,  Gulf  coast; 
Mexico  (domes  near  intrusives) ; 
Trinidad;  Colombia,  Galicia; 
Rumania;  Baku,  Grozny,  Svia- 
toi,  and  Cheleken,  Russia; 
Burma;  Oceanica;  Japan. 

2.  Monoclines  sealed  by 

(a)  Overlying  and  underpin g 
shales,  joining  above  res- 
ervoirs :  Appalachian 
fields,  in  Pennsylvania, 
West  Virginia,  and  Ohio, 
in  part,  some  Mid-Conti- 
nent fields. 

(6)  Faulting :  Los  Angeles,  Cali- 
fornia; Benigadi,  Russia; 
Rumania  and  Galicia  in 
part. 

(c)  Local  cementation  of  reser- 

voir rock:  Glenn  pool, 
Oklahoma;  probably 
many  others. 

(d)  Asphalt:   Coalinga  and  Mc- 
<  Kittrick-Midway-Sunset 

fields,  California  in  part. 

(?)  Unconformities:  Maikop 
Russia,  Douglas,  Wyom- 
ing. 

(/)  Igneous  intrusions:  Tux- 
pam-Tampico  field,  Vera 
Cruz,  Mexico. 

B.  Flat-lying  beds. 

1.  Aclines  including  oil  sands :  Como- 
doroRivadavia(?),!  Argentina  (in 
part) ;  New  Plymouth,  Paritutu, 
New  Zealand. 
2.  Flat-lying  lenses. 

3    Terraces:  Pennsylvania,  Ohio-Indiana, 
Kansas-Oklahoma  field  in  part. 


districts  in  eastern  part  of 


124 


GEOLOGY  OF  PETROLEUM 


C.  Depressed  structural  features. 

1.  Synclines  and  basins:  Catskill  sands  in  Pennsylvania  and  West  Vir- 
ginia; some  parts  of  fields  of  California  and  Galicia;  unimportant 
districts  of  Rocky  Mountain  fields. 

Fissures. 

1.  In  shales:  Florence,  Colorado;  part  of  Salt  Creek,  Wyoming;  part  of 

Cleveland,  Ohio. 

2.  In  schists:  Small  occurrences  of  Santa  Clara,  California  and  Alaska. 

3.  In  igneous  rocks:  Cuba;  part  of  Furbero,  Mexico. 

Combinations  of  two  or  more  structural  features  named  above :  Numerous 
fields. 


D 


E. 


In  Kentucky  the  principal  producing  fields  are  on  anticlines; 
these  include  Irvine,  Campton,  Station,  and  Cannel  City. 

In  Illinois  the  principal  producing  wells  are  along  the  La  Salle 
anticline,  especially  in  domes  that  are  on  and  near  the  crest  of  the 
anticline  in  Lawrence,  Crawford,  Clark,  and  Cumberland 
Counties.  In  the  southwestern  part  of  the  State  oil  is  found  in 


STRUCTURAL  FEATURES  OF  RESERVOIRS       125 


126  GEOLOGY  OF  PETROLEUM 

small  pools  at  or  near  the  crests  of  domes  in  Sandoval,  Marion 
County,  in  Carlinville,  Macoupin  County,  and  in  Greenville,  Bond 
County.  In  the  Carlyle  field,  Clinton  County,  the  beds  are  practi- 
cally horizontal.  Within  short  distances  they  dip  away  from 
the  field  or  become  tight. 

In  many  districts  in  the  Oklahoma-Kansas  region  the  oil  and 
gas  are  clearly  segregated  at  the  tops  of  anticlines  and  domes. 
These  include  the  accumulations  of  the  Gushing,  Ponca  City, 
Garber,  Augusta,  Eldorado,  and  many  other  fields.  East  of  a 
north-south  line  through  Tulsa,  Oklahoma,  the  rocks  are  less 
highly  saturated  and  some  of  the  pools  are  on  structural  terraces. 
Some  are  on  comparatively  regular  monoclines.  In  the  Bartles- 
ville  field,  Oklahoma,  which  has  been  highly  productive,  the  mono- 
clinal  dip  is  nearly  uniform  at  many  places.  Where  it  is  not  the  oil 
is  concentrated  on  slight  upwarps  of  the  undulatory  strata.  In  the 
lola  field  of  Kansas  the  anticlinal  structure  is  barely  perceptible, 
although,  according  to  Orton,  it  may  be  measured  over  very  broad 
arcs.  In  the  western  part  of  the  Kansas  field  the  oil  pools  are 
on  anticlines  and  domes. 

In  the  Red  River  district,  south  of  the  Arbuckle  Mountains,  in 
southern  Oklahoma  and  northern  Texas,  oil  or  gas  or  both  have 
accumulated  in  domes  or  anticlines  in  the  Healdton  (Figs.  29,30), 
Fox,  Graham,  Loco,  and  Duncan  fields.  In  Texas  the  Petrolia 
field  is  a  dome;  the  Electra  and  Burkburnett  pools  are  probably 
anticlinal  deposits  in  areas  complicated  by  faulting.  In  the 
Ranger  and  neighboring  districts  the  oil  pools  are  on  the  Great 
Bend  arch,  below  small  anticlinal  noses  that  are  generally  without 
recognized  closure  at  the  surface.  It  is  thought  by  some  investi- 
gators that  the  amplitudes  of  these  folds  increase  with  depth,  and 
there  is  some  evidence  that  the  folds  are  also  closed  in  depth.  In 
the  Corsicana  field,  Texas,  some  of  the  pools  are  on  an  essentially 
regular  monocline  that  shows  no  closed  folds,  but  others  are  on 
domes  on  the  monocline.  The  Mexia-Groesbeck  gas  field  and  the 
Thrall  oil  field  are  on  domes. 

In  northern  Louisiana  oil  or  gas  or  both  are  found  on  domes  in 
the  Caddo,  Shreveport,  De  Soto-Red  River,  Pelican,  Homer,  and 
Monroe  fields.  In  the  Homer  and  Red  River-De  Soto  fields  pro- 
nounced faults  are  found  near  the  crests  of  the  producing  domes. 
On  the  Gulf  coast  in  Texas  and  Louisiana  oil  is  found  in  many  salt 
domes,  which  are  believed  to  lie  along  axes  of  faulting  and  flexing. 


STRUCTURAL  FEATURES  OF  RESERVOIRS      127 


128  GEOLOGY  OF  PETROLEUM 

In  the  Rocky  Mountain  fields  all  the  oil  in  the  principal  produc- 
ing districts  is  derived  from  deposits  lying  on  domes  and  anticlines. 
In  Wyoming,  which  produces  about  97  per  cent  of  the  oil  and  gas 
from  the  Rocky  Mountain  fields,  more  than  98  per  cent  of  the 
output  (1917)  is  derived  from  fields  having  closed  structure.  Of 
these  fields  about  15  produce  oil,  and  several  others  produce  gas 
only.  All  the  elevated  closed  folds  are  domes  except  one  or  pos- 
sibly two.  In  one  of  these  the  oil  is  accumulated  in  a  fault  trap 
formed  by  an  anticline  plunging  away  from  a  fault.  In  the  Salt 
Creek  field  (Fig.  31),  which  is  the  most  productive  in  Wyoming, 
oil  occurs  on  a  dome.  On  this  dome  and  west  of  it  oil  is  derived  from 
fissures  in  shale.  In  the  Shannon  field,  north  of  the  Salt  Creek 
field,  a  little  oil  has  been  obtained  from  a  small  half  dome  or  nose. 
In  the  Spring  Valley  district,  Uinta  County,  in  the  southwest  cor- 
ner of  the  State,  a  few  thousand  barrels  have  been  obtained  from 
wells  sunk  in  a  syncline. 

In  the  Boulder  district,  Colorado,  oil  is  derived  from  thin  sands 
in  a  shale  and  probably  from  fissures  in  the  shale  also.  In  the 
northern  extension  of  this  district  flowing  wells  were  brought  in 
on  an  anticline. 

In  California  the  oil-bearing  rocks  are  generally  saturated  and' 
the  oil  and  gas  are  found  on  uplifts.  The  Coalinga1  field  is  divided 
into  two  parts,  the  Eastside  and  Westside.  On  the  Westside  the 
oil  has  accumulated  on  a  monocline  where  at  the  outcrop  the  oil 
sands  are  cemented  with  asphalt.  On  the  Eastside  the  oil  is  con- 
centrated below  the  Coalinga  anticline.  In  the  Lost  Hills  district, 
Kern  County,  about  50  miles  southeast  of  the  Coalinga  district, 
oil  is  accumulated  on  the  extension  of  the  Coalinga  anticline.2 
The  Midway  district,  on  the  northeast  flank  of  the  Temblor  Range, 
is  on  a  monocline  on  which  two  subsidiary  folds  are  developed. 
These  folds  have  undulating  crests,  and  the  best  yield,  accord- 
ing to  Arnold  and  Johnson,  is  obtained  on  or  near  the  nodes  of 
the  crests.3  In  the  McKittrick  field  oil  is  found  in  anticlines 
and  in  synclines,  the  rocks  being  overturned,  and  on  monoclines 

ARNOLD,  RALPH,  and  ANDERSON,  ROBERT:  Geology  and  Oil  Resources  of 
the  Coalinga  District,  California.  U.  S.  Geol.  Survey  Bull.  398,  pp.  1-354, 
1910. 

ARNOLD,  RALPH  and  GARFIAS,  V.  R. :  Geology  and  Technology  of  the  Cali- 
fornia Oil  Fields.  Am.  Inst.  Min.  Eng.  Bull  87,  p.  422,  1914. 

ARNOLD,  R.,  and  JOHNSON,  H.  R. :  Preliminary  Report  on  the  McKittrick- 
Sunset  Oil  Region.  U.  S.  Geol.  Survey  Bull  406,  p.  165,  1910. 


STRUCTURAL  FEATURES  OF  RESERVOIRS      129 

where  the  beds  are  healed  by  asphalt.  The  Kern  River  field,  in 
Kern  County,  4  miles  north  of  Bakersfield,  is  on  a  low  dome  on 
a  general  monocline,  superimposed  on  which  are  minor  folds  that 
control  accumulation.1  The  Santa  Clara  district,  in  Ventura  and 
Los  Angeles  Counties,  is  structurally  dominated  by  an  overturned 
anticline.  In  this  field  the  structure  is  exceedingly  complicated. 
One  part  of  the  field  is  situated  in  a  syncline.  A  few  wells  have 
encountered  some  oil  in  schists.  In  the  Santa  Maria  field  oil  is 
accumulated  principally  on  anticlines. 2  In  the  Summerland  field, 
a  small  district  near  shore  and  below  the  Pacific  Ocean,  the  relation 
of  accumulation  to  structure  is  not  clear.  In  the  Los  Angeles  field 
oil  is  accumulated  near  the  crest  of  an  anticline  and  in  a  monocline 
developed  on  its  limb  where  the  oil-bearing  strata  crop  out  (Fig. 
182,  p.  465).  In  part  of  the  field  the  oil  appears  to  be  sealed  in 
by  the  faulting  of  shales  against  the  reservoir  rock.  In  the  Puente 
Hills  district  the  oil  is  found  on  anticlines  and  on  monoclines 
sealed  by  faults.3 

In  foreign  fields  nearly  all  the  petroleum  and  natural  gas  is 
found  in  the  elevated  parts  of  structures. 

Southwestern  Ontario  has  supplied  most  of  the  petroleum  dis- 
covered in  Canada.  The  oil  is  obtained  mainly  from  clearly 
defined  domes,  although  a  little  has  been  obtained  from  open  anti- 
clines and  on  monoclines. 4 

In  Mexico  all  the  large  wells  are  located  where  the  structure  is 
anticlinal  or  domical5  and  the  rock  shows  pronounced  fractures, 
usually  in  the  regions  of  basaltic  intrusives.  In  the  Furbero  dis» 
trict, 6  at  the  south  end  of  the  oil  region,  oil  is  found  in  an  indurated 
and  shattered  shale  above  an  igneous  sill.  In  Trinidad  oil  is  found 
on  anticlines. 

All  the  oil  produced  in  Europe,  Asia,  and  Africa  comes  from 

ARNOLD,  RALPH,  and  GARFIAS,  V.  R.,  op.  cit.,  p.  436. 

ARNOLD,  RALPH,  and  ANDERSON,  ROBERT:  Preliminary  Report  on  the 
Santa  Maria  Oil  District.  U.  S.  Geol.  Survey  Bull.  317,  p.  30,  1907. 

^ELDRIDGE,  G.  H. :  The  Puente  Hills  Oil  District,  Southern  California. 
U.  S.  Geol.  Survey  Bull.  309,  p.  102. 

4 WILLIAMS,  M.  Y. :  Oil' Fields  of  Southwestern  Ontario.  Canada  Dept. 
Mines,  Summary  Rept.,  1918,  part  E,  pp.  30-42,  1919. 

6HuNTLEY,  L.  H. :  The  Mexican  Oil  Fields.  Am.  Inst.  Min.  Eng.  Bull  105, 
p.  2092,  1915. 

6DE  GOLYER,  E.  L. :  The  Furbero  Oil  Field,  Mexico.  Am.  Inst.  Min.  Eng. 
Bull.  105,  pp.  1899-1911,  1915. 


130 


GEOLOGY  OF  PETROLEUM 


III  !* 


:  ! 


strata  later  than  Paleozoic,  except  in  Derbyshire,  England,  where 
oil  has  accumulated  in  a  dome  in  rocks  of 
Paleozoic  age.  With  this  exception  the  oil- 
bearing  strata  are  all  of  Mesozoic  and  of 
Tertiary  age,  much  the  greater  part  being  of 
the  Tertiary. 

In  Alsace  oil  is  found  in  lenses  of  sands 
completely  inclosed  in  marls,  on  monoclines, 
or  sealed  up  the  dip  by  marls  coming  to- 
gether. Some  of  the  lenses  are  faulted  against 
impervious  beds  up  the  dip. 

In  the  Boryslaw  field,  Galicia,  where  the 
petroliferous  beds  are  found  among  strata 
that  are  closely  folded  and  faulted  along 
overthrusts,  the  accumulations  occur  in 
anticlines  and  also  in  gentle  synclines  be- 
tween them.  The  Tustanowice  field  is  on  a 
monocline.  In  the  Opaka-Schodnica-Urcyz 
field,  in  a  block  between  two  profound  faults, 
as  shown  by  Zuber,  oil  is  produced  from  anti- 
clines, synclines,  and  monoclines.  In  western 
Galicia,  which  includes  the  jPotak,  Rogi, 
Rowne,  Krosus  and  other  fields,  the  oil  is 
generally  concentrated  in  domes  and  anti- 
clines. 

In  Rumania  the  bulk  of  the  output  comes 
from  anticlines,  salt  domes,  and  monoclines 
sealed  by  faults. 

In  Baku,  Russia,  the  oil  is  derived  from 
anticlines  and  from  monoclines  on  their 
flanks.  The  principal  structural  features  are 
probably  domes  or  irregular  closed  folds  and 
monoclinal  lenses  (Fig.  32.)  In  the  Holy 
Island  and  Cheleken  fields  oil  is  derived  from 
quaquaversal  uplifts.  The  Grozny  field  is  on 
an  anticline  crossed  by  faults.  The  Maikop 
field  is  on  a  monocline  sealed  at  an  uncon- 
formity. 

In  Burma  the  petroleum  is  derived  from 
anticlines,  especially  from  the  high  places  on  their  undulating 


K 

m 

V.M 


4  i1 
11,1   ll 

lul  III 


^  o 


3S 


STRUCTURAL  FEATURES  OF  RESERVOIRS      131 

4--  ......  Limits  of  production  .....  —  ->] 


Seer  level 


'  Mile 


FIG.  33.  —  Section  of  Dropright  dome,  Gushing  field,  Oklahoma.  Vertical 
and  horizontal  scale  are  the  same.  Shows  curvature  of  Pawhuska  limestone 
from  northwest  corner  of  section  5,  to  northwest  corner  of  section  27  T.  8.  N., 
R.  7.  E.  (Data  from  Beat.} 


— Qft  producing- -~--j 


5ca  /eve/ 


Fault 


FIG.  34. — Section  of  De  Soto-Red  River  field,  Louisiana.  Vertical  and  hori- 
zontal scale  are  the  same.  Shows  curvature  of  Nacotosh  sand  from  northwest 
corner  of  section  14  to  fault  in  section  23.  T.  13  N.  R.  11  W.  (Data  from  Matson 
and  Hopkins.) 


I  \Mile 


FIG.  35.  —  Section  of  Thrall  field,  Texas.  Vertical  and  horizontal  scale  are  the 
same.  Shows  curvature  of  oil-bearing  rock.  (Data  from  Udden  and  Bybee.) 


Mile 


FIG.  36. — Section  of  Volcano  anticline,  West  Virginia.  Shows  curvature  of 
Washington  coal  bed  from  Straight  Fork  Creek  through  town  of  Volcano  to 
Goose  Creek.  Vertical  and  horizontal  scale  are  the  same.  (Data  from  Hennen, 
West  Virginia  Geol.  Survey.) 


W 


Mils 


FIG.  37.  —  Section  of  Salt  Creek  dome,  Natrona  County,  Wyoming.  Shows 
curvature  of  Wall  Creek  sand  from  southwest  corner  of  section  27,  T.  40  N. 
R.  79  W.  to  southwest  corner  of  section  26,  T.  40  N.  R.  78  W.  Vertical  and 
horizontal  scale  are  the  same.  (Data  from  Wegeman,  U.  S.  Geol.  Survey.) 


crests.  The  fields  of  Oceanica  and  Japan  that  have  been  described 
are  on  anticlines. 


132 


GEOLOGY  OF  PETROLEUM 


FIG.  38. — Sketch  plan  of  Yenangyaung  oil  field,  Burma.  The  heavy  black 
line  is  the  red  bed  at  the  base  of  the  Irrawadian  formation.   (After  Pascoe.) 
For  sections  along  A  A',  BB'  and  CC",  see  Fig.  39, 


STRUCTURAL  FEATURES  OF  RESERVOIRS      133 

Amplitudes  of  Anticlinal  Folds  That  Form  Reservoirs.  —  The 

domes  and  anticlines  on  which  oil  and  gas  accumulate  differ  much 
as  to  size  and  elevation.  In  Kansas,  Oklahoma,  and  Texas  pro- 
ductive fields  are  developed  where  the  closure  is  less  than  twenty 
feet  and  the  dips  are  as  low  as  30  feet  to  the  mile.  The  anticline  of 
the  lola  field  of  Kansas,  according  to  Orton,  rises  50  feet  in  8  miles.1 
The  closure  in  the  steepest  part  of  the  Eldorado  field,  Kansas,  is 
more  than  100  feet,  and  in  Augusta,  Kansas,  it  is  approximately 
the  same.  Many  productive  folds  are  larger.  Fig.  33  is  a  section, 
true  to  scale,  of  the  Gushing  field,  Oklahoma.  Fig.  34  is  a  similar 
section,  of  the  DeSoto-Red  River  field,  Louisiana.  Fig.  35  is  a  sec- 
tion of  the  Thrall  field,  Texas.  A  section  of  the  Volcano  anticline 


Recited 


Irr&woidian  Pegu 

Reotbed          Red  beef 


Irrawcrdiotn  *"  -=—       *  I  rra  wad/an 


Pegu 

FIG.  39. — Sections  through  Yenangyaung  oil  field,  Burma,  along  lines  A  A ' 
BE'  and  CC"  in  Fig.  38.   (After  Pascoe.) 

of  West  Virginia  is  shown  in  Fig.  36,  and  one  of  the  Salt  Creek 
dome  of  Wyoming  in  Fig.  37. 

Shapes  of  Anticlines  That  Form  Reservoirs. — Some  anticlines 
and  domes  that  yield  oil  are  fairly  symmetrical — for  example,  the 
Yenangyaung  dome  of  the  Irrawady River  region  of  Burma  (Figs. 
38,  39) ;  the  anticline  at  Bibi-Eibat,  Russia;  and  the  Volcano  dome, 
Ritchie  County,  West  Virginia.  Other  domes  are  unsymmetri- 
cal — for  example,  the  Grass  Creek  dome  and  the  Salt  Creek  dome, 
"Wyoming,  and  the  Oil  Springs  dome,  Ontario.  The  axial  planes 

*ORTON,EDWARD:  Geological  Structure  of  the  lola  Gas  Field.  Geol.  Soc. 
America  Butt.,  vol.  10,  p.  104,  1911. 


134 


GEOLOGY  OF  PETROLEUM 


of  some  domes  and  anticlines  are  steeply  overturned,  as  in  the 
Yenangyat-Singu  field,  Burma;  the  Campina  field,  Rumania;  the 
Boryslaw  field,  Galicia;  and  the  Grozny  field,  in  the  Caucasus 
region  (Fig.  40). 

Oil  and  gas  are  found  in  overturned  folds  whose  axial  planes  lie 
at  low  angles.  In  some  of  the  California  fields  (Fig.  64,  p.  155)  the 
strata  are  so  closely  folded  as  to  form  isoclines,  and  a  well  may 
penetrate  the  same  formation  twice.  Such  folds  producing  oil 
are  apparently  confined  to  fields  that  contain  unconsolidated  or 
partly  consolidated  beds.  Deformation  so  intense  in  thoroughly 
consolidated  rocks  would  generally  result  in  scattering  the  oil 
and  gas. 

Origin  of  Anticlines  That  Form  Reservoirs. — Anticlines  and 
domes  in  general  are  formed  by  compressive  stresses  operating  on 


nt.Meoti'c   +ch.Tchokrak    sm.  Middle  5armafian   &l.  Lower  Sarmott tan 

0  1000  WOO  3000 4000 5000^ 

Scale  H  H  H  H  H  i  i  '  '  '  /> 

FIG.  40. — Section  of  Grozny  oil  field,  Russia.  (After  Thompson.) 

the  earth's  crust.  Many  of  them  are  small  mountain  folds  formed 
when  the  larger  mountain  axes  were  elevated.  This  is  indicated 
by  their  positions  on  monoclines  that  dip  away  from  mountain 
ranges.  Some  of  the  subordinate  folds  are  100  miles  or  more  from 
the  controlling  major  mountain  axes. 

Certain  folds  contain  central  cores  of  igneous  or  sedimentary 
rocks  on  which  the  sedimentary  beds  lie  unconformably.  These 
cores  were  once  hills.  Their  rocks  were  already  compact,  and  in 
the  compacting  and  settling  of  the  overlying  sediments,  which 
were  thicker  away  from  the  core,  a  gentle  inclination  of  the  beds 
away  from  the  core  was  developed.  The  beds  were  thus  arched 
as  if  by  folding,  and  their  initial  dip  away  from  shore  lines  was 


STRUCTURAL  FEATURES  OF  RESERVOIRS      135 

emphasized.  Some  investigators  believe  that  the  compacting  of 
shales  of  varying  thickness  in  Kansas  fields  has  given  rise  to  rec- 
ognizable structural  features.1 

In  the  Tampico-Tuxpam  field  of  Mexico  the  sedimentary  rocks 
dip  eastward  at  low  angles.     At  many  places  igneous  intrusives 


FIG.  41. — Hypothetical  section  of  a  type  of  reservoir  in  principal  Mexican 
oil  field,  according  to  Garfias.  The  reservoir  is  formed  around  a  basaltic 
intrusion  that  penetrated  the  series  of  Cretaceous  limestones  and  shales  and 
only  slightly  disturbed  the  Cretaceous-Eocene  shales.  Black  represents  the 
fractured  and  porous  material  which  constitutes  the  reservoir.  It  is  covered 
by  an  impervious  cap. 


have  been  thrust  into  the  sediments,  and  reservoirs  have  formed 
near  them.     The  intrusions  probably  cause  a  gentle  doming  of  the 

^LACKWELDER,  E.  B  i  The  Origin  of  [Central  Kansas  Oil  Domes.     Amer. 
Asso.  Petrol.  Geologists,  vol.  4,  No.  1,  pp.  89-94,  1920. 


136 


GEOLOGY  OF  PETROLEUM 


rocks,  sufficient  to  influence  accumulation. 1  The  folding  generally 
decreases  toward  the  surface,  where  it  is  at  many  places  difficultly 
recognized  (Fig.  41).  In  the  Ebano  field,  according  to  Garfias,2 
an  igneous  plug  has  domed  the  rocks  it  penetrates  and  on  solidify- 
ing and  sinking  it  has  drawn  the  beds  downward  near  its  contact 


FIG.  42. — Section  of  Spindletop  oil  field,  Texas,  a,  rock  salt;  b,  gypsum; 
c,  limestone.  (After  Lee  Eager.) 


with  them.  This  has  given  rise  to  what  he  terms  the  anticlinal 
ring  and  funnel  structure.  This  structure  is  rare  in  other  oil  fields, 
although  similar  processes  have  operated  in  volcanic  regions  of  the 

western  United  States,  in  which  the 
sedimentary  rocks  dip  away  from  in- 
trusive masses  except  near  the  con- 
tact, where  for  short  distances  they  dip 
toward  the  intrusives. 

Salt  domes  are  structural  domes  that 
contain  bodies  of  salt  (Fig.  42).  In  some 
anticlines  the  lower  rocks  are  thrust 
through  the  upper  ones,  complicating 
the  structure  by  faulting  (Fig.  43). 

Such  is  the  case  in  Rumanian  salt  domes,  where  plugs  of  salt  are 
GARFIAS,  V.  R. :  The  Effects  of  Igneous  Intrusions  on  the  Accumulation  of 
Oil  in  Northeastern  Mexico.     Jour.  Geology,  vol.  20,  p.  666-672,  1912;  The  Oil 
Region  orNprtneastern  Mexico.     Econ.  Geology,  vol.  10,  pp.  195-224,  1915. 

GARFIAS,  V.  R.,  and  HAWLEY,  H.  J.:  Funnel  and  Anticlinal  Ring  Structure 
Associated  with  Igneous  Intrusions  in  the  Mexican  Oil  Fields.     Am.  Inst. 
Min.  Eng.  Trans.,  vol.  57,  pp.  1071-1082,  1917. 
2GARFiAS,  V.  R.,  op.  tit.  (Jour.  Geology). 


5SS,  Masses  of  rock  salt 

'FiG.  43. — Section  of  Baicoi 
oil  field,  Rumania.  (After 
Bosworth.) 


STRUCTURAL  FEATURES  OF  RESERVOIRS      137 

thrust  through  clays  and  sands.  The  sands  are  sealed  above  by 
the  central  mass.  The  structure  shown  at  the  left  in  Fig.  43  is 
essentially  a  fault  trap,  but  differs  from  monoclinal  fault  traps  in 
its  different  arrangement  of  dips.  Structure  of  this  sort  is  probably 
developed  where  rigid  rocks  alternating  with  unconsolidated  weak 
rocks  are  deformed  by  strong  pressure.  Crystalline  salt  is  much 
more  rigid  than  clay  and  sand.  The  thickness  of  the  salt  in  some 
of  the  plugs  is  very  great.  In  some  places  the  salt  beds  are  prob- 
ably on  edge.  In  the  salt-dome  fields  of  Texas  and  southern 
Louisiana  the  domes  apparently  occur  along  axes  of  deformation 
by  folding  and  faulting. 

Arrangements  of  Anticlinal  Folds  That  Form  Reservoirs. — In 
some  regions  oil  lies  in  lines  of  pools  that  are  elevated  portions  or 


FIG.  44. — Ideal  sketch  showing  oil  accumulated  principally  on  the  lower 
anticline  or  the  one  on  the  basinward  side  of  the  larger  fold;  the  accumulation 
is  greatest  on  the  basinward  limb  of  the  anticline.  Black  represents  oil  and  gas. 

nodes  along  anticlinal  crests.  On  the  Shoshone  anticline,  which 
lies  east  of  the  Wind  River  Mountains,  Wyoming,  four  domes  or 
elevated  portions  of  the  anticline  yield  oil  or  gas.  Oil  is  found  in 
several  fields  on  high  parts  of  the  Coalinga  anticline,  California. 
Along  the  axes  in  the  Yenangyaung  and  Yenangyat-Singu  fields, 
in  Burma,  oil  and  gas  have  accumulated  at  several  places  where 
the  crests  of  the  anticlines  are  higher  than  elsewhere. 

In  other  regions  the  oil  pools  in  domes  or  anticlines  lie  rudely  in 
curved  lines  corresponding  to  axes  of  deformation.  In  still  other 
places  the  pools  are  very  irregularly  distributed,  owing  doubtless 
either  to  deformation  at  two  periods  or  to  gentle  deformation 
without  much  definition.  As  a  rule  the  elevated  crests  that  lie 
lower  are  more  productive  than  the  higher  ones  in  the  same  series 
(Fig.  44).  Thus  in  Oklahoma  the  Gushing  field  is  more  productive 
than  the  Barstow  region,  and  the  Glenn  pool  is  more  productive 
than  the  region  about  Muskogee.  In  the  region  near  Red  River, 
southern  Oklahoma,  the  oil  fields  are  grouped  near  the  outer  border 


138  GEOLOGY  OF  PETROLEUM 

of  the  Permian  rocks,  which  dip  southwestward  along  Red  River 
and  rise  again  south  of  the  river,  forming  a  deep  salient  or  embay- 
ment.  The  Healdton  dome,  which  is  a  basinward  fold,  is  more 
productive  than  those  which  are  higher  up,  including  the  Fox, 
Graham,  and  others.  This  relation  is  clearly  shown  in  the  Big 
Horn  Basin,  Wyoming  (p.  400),  where,  as  stated  by  Hewett  and 
Lupton,  the  more  productive  anticlines  are  those  which  lie  basin- 
ward.  In  this  basin  there  are  two  circles  of  anticlines,  of  which 
the  inner  is  much  more  highly  productive  than  the  outer.  Thus 
the  Elk  Basin,  Byron,  Greybull,  Torchlight,  and  Bonanza  domes 
are  more  productive  than  the  Lovell,  Spence,  Midnight,  Tensleep, 
and  Bud  Kimball,  which  yield  a  little  oil  or  are  barren.  On  the 
west  side  of  the  basin  the  Warm  Springs,  Grass  Creek,  Little 
Buffalo,  Oregon  Basin,  and  Cody  anticlines  are  more  productive 
than  the  Rawhide,  Gooseberry,  Wagonhound,  and  Hamilton.  The 
oil  evidently  migrated  upward  from  the  basin  into  the  elevated 
portions,  and  the  gathering  ground  on  the  basinward  side  is  much 
greater  than  on  the  side  toward  the  mountains.  Moreover,  in  the 
outer  circle  of  anticlines,  the  ground  water  doubtless  has  entered 
and  in  some  places  washed  the  beds  clean  of  any  oil  they  may  have 
once  possessed.  Evidence  of  this  lies  not  only  in  oil  springs,  but 
also  in  the  fact  that  some  of  the  folds  carry,  below  the  oil,  water 
that  is  not  highly  saline  compared  with  waters  of  other  fields. 

A  small  dome  near  the  center  of  a  basin  obviously  has  a  small 
gathering  ground  and  should  not  be  expected  to  contain  a  large 
deposit. 

Segregation  of  Oil  on  Basinward  Sides  of  Folds. — In  many  fields 
the  portion  of  the  oil  sand  that  carries  oil  and  gas  is  not  symmetri- 
cal with  respect  to  the  fold.  As  a  rule  it  descends  farther  down 
the  flank  of  the  gentle  limb  than  it  does  down  the  steep  flank. 
This  is  noteworthy  in  the  Yenangyat-Singu  field  of  Burma,  where 
on  a  long,  sharp,  unsymmetrical  anticline  (p.  556)  practically  all  the 
wells  are  west  of  the  crest  of  the  fold,  on  its  gentler  flank.  In  the 
Big  Horn  basin,  Wyoming,  the  basinward  flank  almost  invariably 
has  the  greater  accumulation.  In  the  Salt  Creek  field  (in  the  first 
Wall  Creek  sand)  the  oil  blanket  extends  deeper  on  the  northeast 
side  of  the  dome,  which  has  a  greater  gathering  ground.  In  the 
Gushing  pool  the  accumulation  is  greater  on  the  basinward  side, 
and  some  of  the  sands  that  yield  oil  on  the  west  side  of  the  dome 
yield  gas  only  on  the  east  side.  These  observations  show,  that  in 


STRUCTURAL  FEATURES  OF  RESERVOIRS       139 

many  folds  the  gravitational  separation  is  not  perfect.  Beal1  sug- 
gests that  the  gas  accumulates  first  and  banks  up  near  the  crest  of 
the  fold  and  prevents  the  oil  that  collects  on  the  side  where  the 
gathering  ground  is  greatest  from  passing  over  to  the  opposite  side. 

In  steep  symmetrical  domes,  containing  sands  that  are  every- 
where permeable,  the  contact  between  oil  and  water  would  norm- 
ally be  flat.  If  higher  at  one  point  than  another,  the  water  would 
descend  by  gravity  and  push  the  oil  up  where  it  is  lowest.  At 
many  places  however,  where  gravitational  separation  is  clearly 
indicated  by  the  position  of  the  accumulation  with  respect  to  the 
structure,  the  contact  between  the  water  and  the  oil  is  not  level. 
This  condition  may  be  due  to  tightness  of  the  sands  in  places,  which 
prohibits  free  circulation  of  oil  around  the  dome  on  nearly  level 
lines.  The  maximum  accumulations  of  oil  on  the  domes  of  Osage 
County,  Oklahoma,  are,  according  to  Mason,2  on  the  north  and 
northwest  sides  of  the  domes.  The  maximum  accumulations  of 
oil  and  gas,  however,  are  not  all  on  the  long  limbs  of  "the  folds. 
In  the  Caddo  and  Crichton  fields,  Louisiana,  according  to  Crider, 3 
in  certain  areas  short  limbs  are  most  productive. 

In  the  Gushing  field,  Oklahoma,  in  the  Layton  and  Wheeler 
sands,  the  contact  is  gently  inclined  in  the  direction  of  the  dip  of 
the  strata.  This  attitude  may  be  due  in  part  to  differences  in 
porosity  or  to  differences  in  the  size  of  the  pores  in  the  reservoir 
rocks. 

RESERVOIRS  IN  MONOCLINES 

A  considerable  number  of  the  world's  oil  and  gas  fields  lie  on 
monoclines  that  are  sealed  in  various  ways.  Monoclines  may  be 
sealed  where  impervious  rocks  meet  above  the  reservoir  rock  (Fig. 
45),  at  impervious  fault  planes  or  where  faults  throw  impervious 
rocks  against  the  reservoir  rocks  (Fig.  46),  where  the  sands  become 
impervious  by  cementation  of  their  interstices  or  where  the  inter- 
stices were  filled  with  clay  particles  when  the  sands  were  deposited 

JBEAL,  C.  H. :  Geologic  Structure  in  the  Gushing  Oil  and  Gas  Field,  Okla- 
homa, and  Its  Relation  to  Oil,  Gas,  and  Water.  U.  S.  Geol.  Survey  Bull.  658, 
p.  44,  1917. 

2MASON,  S.  L. :  A  Statistical  Investigation  of  the  Effects  of  Structure  Upon 
Oil  and  Gas  Production  in  the  Osage.  Amer.  Assoc.  of  Petrol.  Geologists, 
vol.  3,  pp.  407-417,  1919. 

CRIDER,  A.  F. :  Oil  and  Gas  Possibilities  in  Mississippi.  Bull,  of  the  South- 
western Assoc.  of  Petrol.  Geologists,  vol.  1,  pp.  152-155,  1917. 


140 


GEOLOGY  OF  PETROLEUM 


(Fig.  47),  or  where  the  oil  itself  at  or  near  the  surface,  on  drying 
hardens  to  form  asphalt  (Fig.  48).  A  few  oil  fields  are  formed 
where  a  tilted  eroded  petroliferous  series  is  covered  unconf ormably 
by  a  later  series.  If  permeable  strata  such  as  conglomerates  and 


FIG.  45. — Sketch  showing  reservoir  sealed  by  impervious  rocks  overlying  and 
underlying  the  reservoir  rock  and  joining  above  the  reservoir. 

sandstones  are  laid  down  upon  the  petroliferous  strata,  the  beds  of 
the  later  series  may  carry  oil.  If  muds  or  clays  cover  the  petrolif- 
erous bed,  gas,  oil,  and  water  will  probably  be  segregated  in  the 
lower  bed.  Reservoirs  are  found  at  unconformities  in  many  fields. 
In  the  Maikop  field,  on  the  north  flank  of  the  Caucasus,  Russia, 


FIG.  46. — Sketch  showing  reservoir  sealed  by  fault  bringing  oil  sand  against 

impervious  rocks. 


oil  has  accumulated  in  a  sand  that  was  deposited  upon  an  older 
hilly  surface  and  in  turn  covered  by  a  impervious  bed  so  that  it 
is  effectively  sealed  (Fig.  57,  p.  150).  In  the  Tampico-Tuxpam  field, 
Vera  Cruz,  Mexico,  petroliferous  beds  are  sealed  by  igneous  intrus- 


FIG.  47. — Sketch  showing  reservoir  sealed  by  tight  sand.  Black  is  oil  and  gas. 

ives  that  cut  across  the  beds.  It  is  obvious  that  monoclines  sealed 
by  impervious  rocks  joining  above  the  reservoir  rock  and  mono- 
clines sealed  by  local  cementation  and  at  unconformities  are  dis- 
covered with  greater  difficulty  than  monoclines  sealed  by  other 


STRUCTURAL  FEATURES  OF  RESERVOIRS      141 


EXPLANATION 


Sand,clay.shale,andgravel.  Beds  containing  oil  Bedscontamingtar  Beds  containing  water 

Horizontal  scale 
0        |         [         |         <     i.ooo  2,000  Feet 

Vertical  scale 


FIG.  46. — Stereogram  showing  reservoir  sealed  by  asphalt  forming  in  oil  sand 
near  the  surface,  Sunset-Midway  field,  California.  (After  Pack,  U,  S.  Geol, 
Survey.) 


142 


GEOLOGY  OF  PETROLEUM 


processes.     Oil  pools  in  such  positions  are  discovered,  more  often 
than  otherwise,  by  "wildcat"  drilling  or  by  wells  sunk  for  water. 

Monoclines  Sealed  By  Overlying  and  Underlying  Clays  or 
Shales  Joining  Above  Reservoirs. — Monoclines  sealed  by  clays  or 
shales  are  found  at  many  places.  In  the  Appalachian  geosyncline, 
which  includes  many  of  the  great  oil  pools  of  the  United  States,  the 


FIG.  49. — Map    showing    location    of    "Clinton"    gas    field,    Ohio.  (After 

Bownocker.) 

sands  generally  thin  out  toward  the  west.  The  land  mass  that 
supplied  the  sediments  during  Paleozoic  time  was  southeast  of  the 
oil  field.  At  the  end  of  the  Paleozoic  era  the  strata  were  folded 
and  the  great  Appalachian  geosyncline  was  formed.  Pa/allel  to 
the  axis  of  the  geosyncline  there  are  many  subordinate  folds. 
Where  the  porous  strata  rise  west  of  an  axis  of  such  a  fold  or  west 


STRUCTURAL  FEATURES  OF  RESERVOIRS       143 


of  the  axis  of  the  great  geosyncline,  accumulations  of  oil  and  gas  are 

likely  to  be  found.  In  eastern  Ohio  (Fig.  49),  where  the  "Clinton'  ' 

sand  thins  out  up  the  dip,  the  shales  above  and  below  it  come 

together.  The  upper  part  of 

this  sand  contains  gas  under 

great   pressure.  From   Cleve- 

land   southward    to    Jackson 

County,    a    distance    of    170 

miles,  wells  producing  gas  are 

sunk  to  this  reservoir  at  many 

places.  The  general  relations 

in  the  Appalachian  field  are 

illustrated  by  Fig.  50. 

In  Eastern  Ohio  oil  and  gas 
are  found  in  the  Berea  sand, 
near  the  lower  part  of  the 
Mississippian.  l  The  Sunbury 
shales  lie  above  the  Berea,  and 
the  Bedford  shales  below  it. 
The  Berea  yields  oil  or  gas  in 
many  counties. 

Approximately  along  the 
area  indicated  by  the  line 
X-  Y  in  Fig.  51,  there  is,  ac- 
cording to  Panyity,  a  note- 
worthy change  in  the  char- 
acter of  the  sedimentary  rocks. 
East  of  the  line  and  parallel  to 
it,  where  the  sand  is  thin  and 
lenticular,  the  most  productive 
fields  are  found.  These  include 
the  fields  of  Barnesville,  Tem- 
perance ville,  Summerfield, 
Macksburg,  Dudley,  and 
others.  East  of  the  gas  fields, 
down  the  dip,  are  the  most 
productive  Berea  oil  pools. 
In  places  where  anticlinal  structure  is  present  the  positions  of 


,  L.  S.  :  Lithology  of  the  Berea  Sand  in  Southeastern  Ohio  and  Its 
Effect  on  Production.     Am.  Inst.  Min.  Eng.  Bull  140,  pp.  1317-1320,  1917. 


144 


GEOLOGY  OF  PETROLEUM 


the  gas,  the  oil,  and  the  water  are  in  accord  with  the  structural 
theory  (Fig.  52).  The  controlling  factor  in  most  of  these  pools, 
however,  is,  according  to  Panyity,  the  western  limit  of  the  sand. 
West  of  the  line  X-  Y  there  is  a  water-bearing  sand.  Near  Byes- 
ville  small  gas  pools  are  developed  on  minor  uplifts  above  the 
water.  The  only  field  of  any  considerable  size  developed  west  of 
the  line  is  the  Corning  pool. 


1  Byesville 

2  ilcConnclsville 
Guysville 

4     Bcd/oid 

ixaic  of  Jlilo 
10  20 


FIG.  51. — Sketch  map  showing  position  of  certain  oil  pools  in  Berea  sand  in 
southeastern  Ohio.  Oil  is  found  in  sealed  monocline  east  of  line  X-Y.  (After 
Panyity.}  For  section  along  AB  and  CD  see  Fig.  52. 


Monoclines  Sealed  By  Faults. — Some  faults  afford  channels 
along  which  fluids  escape.  Other  faults  are  accompanied  by  finely 
ground  clay  that  seals  the  opening,  making  the  fault  impervious. 
Faults  that  cross  shaly  strata  or  other  soft  rocks  are  generally 
impervious.  Some  oil  pools  are  on  monoclines  sealed  up  the  dip  by 
faults.  In  the  Appalachian  fields  no  monoclines  of  this  character 
have  been  described,  nor  have  they  been  recognized  in  western 
Ohio,  Indiana,  or  Illinois.  In  Kentucky  the  Irvine  field  is  devel- 
oped along  a  faulted  anticline,  but  at  most  places  the  reservoir  has 
been  sealed  by  folding,  or  by  folding  and  faulting  together.  (See 
Fig.  106,  p.  241.)  In  Oklahoma,  southeast  of  Gushing  and  soutlu 


STRUCTURAL  FEATURES  OF  RESERVOIRS       145 

west  of  the  Glenn  pool,  oil  has  accumulated,  probably  in  places 
where  faults  sealed  the  petroliferous  sands  above,  but  the  details 
of  the  structure  in  this  area  have  not  been  made  public.  Where 
a  plunging  anticline  is  faulted  across  the  strike  a  "fault  trap"  is 
formed.  In  Wyoming  part  of  the  oil  produced  in  the  Big  Muddy 
field  was  obtained  on  an  anticline  plunging  away  from  a  fault.  In 


Sunbury  shar/e 
Bere&f  Wafer  J 
Shcxle  "break  "  15 

Berecr  (pay  sand)       20 ' 
Bedford  shales  35 ' 


FIG.  52. — Sketch  showing  (a)  section  of  Berea  sand  and  adjacent  strata; 
(6)  reservoir  in  Berea  sand  on  monocline  (line  CD,  Fig.  51)  and  (c)  reservoir 
in  Berea  sand  on  monocline  and  gas  in  anticline  (on  line  AB,  Fig.  51.)  All  in 
southeastern  Ohio.  (After  Panyity.} 

the  Los  Angeles  field,  California,  a  fault  has  apparently  sealed  a 
petroliferous  stratum  (Fig.  184,  p.  464).  At  Binagadi,  Russia,  the 
reservoir  rocks  are  faulted  (Fig.  53).  Where  faults  bring  perme- 
able sands  into  juxtaposition,  the  seal  is  less  likely  to  prove 
effective,  as  is  shown  by  Fig.  54. 


146 


GEOLOGY  OF  PETROLEUM 


Monoclines  Sealed  By  Local  Cementation  of  the  Reservoir 
Rock. — Oil  migrates  up  the  dip.  If  it  reaches  a  place  where  the 
reservoir  rock  is  impervious  it  will  halt.  The  reservoir  stratum 
may  be  made  impervious  by  deposits  of  clay,  calcite,  iron  oxide,  or 
carbonate  in  the  interstices  between  the  grains.  Some  petrolif- 


FIG.  53. — Section  of  Binagadi  oil  field,  Russia.  6,  Freshwater  beds,  Miocene; 
c,  Lower  Miocene;  s,  Spiralis  beds.   (After  Thompson.} 

erous  strata  are  impervious  at  places  where  clay  was  deposited 
when  the  strata  were  laid  down.  Whatever  the  cause,  the  imper- 
vious portion  of  the  stratum  will  delay  or  stop  migration  and  cause 


FIG.  54. — Diagrammatic  cross-section  showing  (at  A)  an  accumulation  of 
oil  and  gas  caused  by  a  fault  and  (at  B]  a  possible  condition  under  which  a 
fault  may  not  seal  a  reservoir.  (After. Path.} 

an  accumulation.     The  famous  Glenn  pool,  in  Oklahoma,  is  on  a 

fluted  monocline,  and  the  accumulation  of  oil  is  believed  to  be  due 

in  part  to  changes  in  the  character  of  the  sands  above  the  oil  pool. 

Monoclines  Sealed  By  Asphalt. — Some  reservoirs  on  monoclines 


STRUCTURAL  FEATURES  OF  RESERVOIRS       147 

are  sealed  above  by  tarry  products  that  have  resulted  from  hard- 
ening of  materials  in  the  oil  (Fig.  55).  Reservoirs  containing  the 
heavier  asphaltic  oils  are  more  generally  sealed  in  this  manner 
than  reservoirs  containing  the  lighter  paraffin  oils,  although  vents 
leading  from  reservoirs  are  known  to  contain  both  the  asphaltic 
and  the  paraffin  bitumens.  This  subject  is  treated  in  connection 
with  a  discussion  of  bituminous  dikes  (pp.  29  to  32).  It  is  gener- 
ally supposed  that  the  tarry  products  result  from  partial  oxidation 
of  the  oil  or  from  reaction  of  the  oil  with  ground  water  or  from  loss 
of  gases  and  the  lighter  liquids  by  partial  evaporation.  At  some 
places  bituminous  solids  have  formed  at  depths  from  1,000  to  2,000 
feet  below  the  surface  and  it  appears  improbable  that  atmospheric 


Approximate  scale 
o        i.poo     a.opo     3.000     4,000     5,000  Feet. 


FIG.  55. — Diagram  showing  relations  of  productive  oil  zones  in  the  vicinity  of 
Fellows,  Midway-Sunset  district,  California.  (After  Pack.) 


oxygen,  under  the  conditions,  should  be  effective  at  such  great 
depths. 

The  best  known  fields  of  which  the  reservoir  rocks  are  sealed  by 
bitumens  are  the  Coalinga  field  and  the  Sunset-Midway  field  of 
California.  In  both  of  these  fields  highly  productive  reservoirs 
are  sealed  by  tar  plugs.  In  the  Sunset-Midway  district1  the  reser- 
voirs containing  the  oil  are  sealed  up  by  tarry  oil  or  tar  which  is 
formed  by  the  interaction  of  the  mineralized  waters  and  the  hydro- 
carbons that  compose  the  oil.  It  is  a  reaction  which  results  in  the 

^ACK,  R.  W.:  The  Sunset-Midway  Oil  Field,  California.  U.  S.  Geol. 
Survey  Prof.  Paper  116,  p.  87,  1920. 


GEOLOGY  OF  PETROLEUM 

iction  of  sulphate  water  to  form  sulphides  and  the  addition  of 
th^ulphur  or  sulphides  to  the  oil. 1 

*lrt  cording  to  Pack2,  the  reactions  that  result  in  the  formation  of 
tarry  products  may  be  divided  into  two  classes,  one  that  takes 
place  near  the  surface;  another  at  greater  depth,  in  many  places  at 
the  very  base  of  the  oil  zone,  below  the  beds  containing  the  pro- 
ductive oil  sands. 

The  reactions  that  take  place  close  to  the  surface,  particularly 
along  the  outcrop  of  the  oil-bearing  beds,  result  in  sealing  up  the 
outcrop  and  preventing  the  escape  of  the  oil.  The  extent  to  which 
the  oil  undergoes  alteration  is  evidently  far  greater  near  the  surface 
than  it  is  at  depth,  for  the  deposits  of  tar  and  of  sulphur  are  greater 


FIG.  56A. — Sketch  of  section  showing  oil  and  gas  (black)  in  porous  deposits 
that  rest  unconf  ormably  on  a  tilted  series  of  oil  sands  and  carbonaceous  shales. 


FIG.  56B. — Sketch  of  section  showing  accumulation  of  oil  and  gas  above  water 
in  a  tilted  bed  overlain  unconf  ormably  by  an  impervious  bed. 

there.  The  surface  water  characteristically  contains  more  sul- 
phates than  the  waters  at  greater  depth,  and  the  oxidation  of  the 
oil  is  aided  to  a  large  extent  by  other  oxidized  products  in  the  rocks 
that  lie  close  to  the  surface,  or  by  exposure  to  the  air  itself.  Not 
only  are  the  oils  at  or  near  the  surface  changed  more  or  less  com- 
pletely to  tar,  but  the  sulphate  waters  are  changed  so  completely 
that  great  quantities  of  free  sulphur  are  formed,  and  deposits  of 
native  sulphur  such  as  the  one  occurring  south  of  Old  Sunset  result. 
Sulphur  is  widely  scattered  along  the  foothills  in  which  the  oil 
sands  crop  out. 

ROGERS,  G.  S. :  Chemical  Relations  of  the  Oil-Field  Waters  in  San  Joa- 
quin  Valley,  California  (preliminary  report).  U.  S.  Geol.  Survey  Bull  653, 
119  pp.,  1917. 

20p.  cit.,  p.  88. 


STRUCTURAL  FEATURES  OF  RESERVOIRS       149 

In  the  Midway  region,  according  to  Pack,1  there  is  clear  evidence 
that  oil  has  been  hardened  by  surface  water  to  depths  800  or 
1,000  feet.  The  effect  of  the  deeper  waters  on  the  oil  is  not  so  exten- 
sive as  that  of  the  surface  waters,  but  it  is  evident  none  the  less,  for 
at  many  places  where  water  is  found  in  the  oil  sand  a  deposit  of  tar 
or  heavy  oil  separates  the  portion  of  the  sand  occupied  by  oil  from 
that  occupied  by  water.  The  reason  for  the  lesser  effect  of  the 
deeper  waters  and  thus  for  the  smaller  amounts  of  tar  in  the  deeper 
sands  is  evidently  the  fact  that  the  waters  in  the  deeper  sands  con- 
tain normally  a  far  smaller  amount  of  sulphate  than  the  surface 
waters. 

Monoclines  Sealed  at  Unconformities. — At  many  places  tilted 
beds  are  covered  by  relatively  flat-lying  beds.  Unconformities 
are  favorable  places  for  accumulation,  because  the  younger 
deposits  commonly  include  coarse  sandstone  or  conglomerate  near 
the  base  (Fig.  56A).  Some  monoclines,  it  is  said,  are  sealed  by 
impervious  beds  that  cover  the  tilted  beds  by  overlapping  them 
(Fig.  56B). 

If  the  underlying  older  strata  contain  sands  or  other  porous  rocks 
covered  by  shales  and  the  sands  become  saturated  with  petroleum 
and  water  the  petroleum  will  rise  toward  the  surface  and  be  halted 
or  diverted  when  it  reaches  the  impervious  cover.  The  line  or 
zone  of  junction  is  rarely  level,  and  accumulation  is  unequal  at 
different  places  where  the  porous  bed  is  covered.  If  the  junction 
is  sealed  at  the  high  end  by  warping  or  at  a  place  where  the  reser- 
voir rock  is  tight,  a  trap  is  formed  in  which  the  oil  or  gas  or  both 
may  find  lodgment. 

In  Brenning  Basin,  in  the  Douglas  oil  and  gas  field,  near  Douglas, 
Wyoming,  the  nearly  flat  White  River  (Tertiary)  beds  rest  on 
tilted  Cretaceous  strata  that  include  nearly  all  the  beds  of  the 
Colorado  and  Montana  groups  (Cretaceous),  which  are  produc- 
tive elsewhere  in  Wyoming.  Barnett2  states  that  the  petroleum 
in  migrating  upward  along  bedding  planes  and  through  porous 
sandstone  finds  a  barrier  when  it  reaches  the  White  River  forma- 
tion, so  that  oil  and  gas  accumulate  near  the  contact.  They  pene- 
trate the  White  River  beds  only  where  they  encounter  porous 
material  or  fault  planes. 

I0p.  til.,  p.  88. 

BARNETT,  V.  F. :  The  Douglas  Oil  and  Gas  Field,  Converse  County,  Wyom- 
ing. U.  S.  Geol.  Survey  Bull.  541,  p.  69,  1914. 


150 


GEOLOGY  OF  PETROLEUM 


The  structural  conditions  are  somewhat  similar  in  the  Healdton  * 
pool,  south  of  the  Arbuckle  Mountains,  Oklahoma,  where  Pennsyl- 
vanian  strata  rest  on  steeply  tilted  Ordovician  beds.1  A  little  of 
the  Healdton  oil  was  probably  originally  in  the  Ordovician  beds, 

where  they  are  covered  by  the  Penn- 
sylvanian  shales.  The  principal  part 
of  the  output,  however,  is  derived 
from  Pennsjlvanian  rocks. 

In  the  Madill  pool,  Oklahoma, 
just  south  of  the  Arbuckle  uplift, 
folded  Paleozoic  sediments  dip  at 
at  high  angles.  Above  them  are  Cre- 
taceous rocks  that  lie  nearly  flat. 
The  lowest  member  of  the  Cre- 
taceous, the  Trinity  sand  and 
gravel,  is  saturated  with  oil  that  is 
probably  derived  from  the  under- 
lying Carboniferous  strata,2  which 
are  highly  productive  in  this  region. 
In  the  McKittrick-Midway-Sun- 
set  region,  California,  the  Monterey 
(lower  Miocene)  and  Santa  Marga- 
rita formations,  which  lie  in  a  con- 
formable series,  are  tilted,  and  the 
McKittrick  .(upper  Miocene)  over- 
lies them  unconformably. 3  The 
oil  is  believed  to  have  originated  in 
the  diatomaceous  shales  of  the 
Monterey  and  to  have  migrated  to 
the  sandy  layers  in  the  Monterey  or 
to  the  sands  and  gravels  of  the  un- 
1PowERS,  SIDNEY:  The  Healdton  Oil 
Field,  Oklahoma.  Econ.  Geology,  vol.  12, 
pp.  594-606,  1917. 

2TAFF,  J.  A.,  and  REED,  W.  H.:  The 
*  Madill  Oil  Pool,  Oklahoma.     U.  S.  Geol. 

Survey  Bull  381,  pp.  504-513,  1910. 

HUTCHINSON,  L.  L. :  Rock  Asphalt,  Asphaltite,  Petroleum,  and  Natural  Gas 
in  Oklahoma.     Oklahoma  Geol.  Survey  Bull.  2,  p.  252,  1911. 

•ARNOLD,  RALPH,  and  GARFIAS,  V.  R. :  Geology  and  Technology  of  the  Cali- 
fornia Oil  Fields.     Am.  Inst.  Mm.  Eng.  Bull.  87,  pp.  383-470,  1914. 


STRUCTURAL  FEATURES  OF  RESERVOIRS      151 


conformably  overlying  McKittrick  formation.  With  a  few  excep- 
tions the  productive  sands  of  the  region  are  at  the  base  of  the 
McKittrick,  above  the  unconformity. 

In  the  districts  mentioned  above  oil  has  originated  in  the  older 
series,  below  the  unconformity,  and  has  accumulated  in  the  older 
series  where  it  is  sealed  in  or  has  passed  into  the  porous  beds  of  the 
younger  series.  Examples  are  known,  however,  where  the  oil  has 
originated  in  the  younger  series  and  has  accumulated  in  sandy  beds 
of  that  series  where  they  rest  upon  an  old  erosion  surface  that 
existed  before  the  reservoir  rocks  were  formed  and  where  the 
reservoir  rocks  are  sealed  above  by  overlapping  impervious  rocks. 
The  best^ known  example  is  theMaikop  field  (Fig.  57), on  the  north 
side  of  the  Caucasus  Mountains,  about  300  miles  west  of  Grozny, 
Russia.  Here  Tertiary  beds  dip  away  from  an  erosion  surface  of 
Cretaceous  rocks.  The  oil  is 
accumulated  in  Tertiary  sands, 
which  are  covered  by  later  im- 
pervious beds,  and  in  places  it 
rises  to  the  contact  of  the 
sands  with  the  Cretaceous,  as 
is  shown  in  Fig.  57.  The  over- 
lying beds  extend  farther  over 
the  ancient  surface  of  the  Cre- 
taceous rocks,  overlapping  the 
petroliferous  sands.  As  shown 

in  the  sketch  by  Thompson,1  the  significant  structural  feature  is 
not  the  fold  in  the  Cretaceous  rocks  but  the  steep  eroded  surface 
of  the  Cretaceous,  which  is  progressively  overlapped  by  the 
Tertiary  strata. 

In  Ontario,  in  Quebec,  and  probably  also  in  northern  New 
York,  according  to  F.  G.  Clapp,2  gas  is  found  in  basal  sandstones 
overlying  crystalline  rocks  (Fig.  58).  The  structure  of  these  beds 
has  not  been  described  in  detail.  The  accumulations  are  probably 
due  to  the  larger  openings  in  coarser  material  near  the  base  of  the 
formation. 

THOMPSON,  A.  B. :  The  Relation  of  Structure  and  Petrology  to  the  Occur- 
rence of  Petroleum.  Inst.  Min.  and  Met.  Trans.,  vol.  20,  p.  258,  1911. 

TRENCH,  R.  H. :  Discussion  of  THOMPSON'S  Paper.     Idem,  p.  247. 

2CLAPP,  F.  G.:  A  Proposed  Classification  of  Petroleum  and  Natural  Gas 
Fields,  Based  on  Structure.  Econ.  Geology,  vol.  5,  p.  519,  1910. 


FIG.  58. — Gas  pool  at  unconformity, 
New  York.   (After  Clapp.} 


152 


GEOLOGY  OF  PETROLEUM 


-r-2000 


Surface  sand*. 

Clays,  marls 
Sands.shales 

&ncl thin 
limestones 


beetle  of  miles 

FIG.  59. — Hypothetical  cross-section  of  a  volcanic  plug  in  the  coastal  plain 
of  Mexico.   (After  Clapp.) 

Monoclines  Sealed  By  Igneous  Intrusions. — In  the  Tampico- 
Tuxpam  region,  Mexico,  oil  accumulations  are  found  in  areas  where 


FIG.  60. — Hypothetical  section,  according  to  Garfias,  illustrating  basalt 
intruding  the  oil  series  of  Mexico  and  reaching  the  surface.  Black  represents 
the  places  that  are  favorable  for  oil  accumulation.  The  plug  is  larger  near  the 
surface,  where  expansion  is  easier,  owing  to  lighter  load. 


STRUCTURAL  FEATURES  OF  RESERVOIRS      153 

dikes  or  other  igneous  bodies  cut  across  the  petroliferous  beds. 
As  a  rule  the  intrusion  appears  to  have  been  attended  by  uplifting 
of  the  strata  into  domes.  Clapp  described  an  occurrence  where 
the  strata  are  uplifted  on  both  sides  of  a  plug  (Fig.  59).  In  an 
example  illustrated  by  Garfias  (Fig.  60)  there  is  practically  no 
doming  of  the  strata. 

RESERVOIRS  IN  FLAT-LYING  BEDS 

Aclines. — Aclines  are  bodies  of  rock  that  lie  essentially  flat.  In 
such  rocks  large  accumulations  of  oil  are  rare.  The  Rivadavia 
field,  Argentina,  is  on  a  broad  monocline  that  dips  east.  The  rocks 
are  so  nearly  flat  that  the  field  has  been  regarded  as  aclinal. 

Producing 


portion 


FIG.  61. — Ideal  section  of  Gaines  Pool,  Pennsylvania,  showing  its  relation 
to  supposed  change  of  depth.  A,  oil  sand;  B,  brink  of  terrace  where  oil  is 
supposed  to  have  accumulated.  (After  Fuller.) 


FIG.  62. — Ideal  section  showing  position  of  oil  accumulation  on  a  terrace. 
If  the  oil  migrates  upward  as  it  does  in  saturated  rocks,  it  will  accumulate 
near  A.  If  it  migrates  downward  it  will  accumulate  near  B. 

Recently,  however,  it  has  been  shown  that  the  oil  has  accumulated 
in  very  shallow  domes.  (See  p.  592.)  In  the  New  Plymouth  field, 
New  Zealand,  no  elevated  structural  features  are  recognized. 

Terraces. — There  is  apparently  a  lower  limit  of  inclination 
beyond  which  petroleum  will  not  migrate  up  the  dip. *  This  limit 
depends  on  the  size  of  the  openings,  gas  pressure,  and  the  viscosity 
of  the  oil.  Where  there  is  a  change  from  a  dip  up  which  oil  will 
move  to  one  up  which  oil  will  not  move  an  accumulation  is  likely 
to  take  place  (Fig.  61).  If  salt  water  is  associated  with  the  oil  and 

^LAPP,  F.  G. :  Revision  of  the  Structural  Classification  of  Petroleum  and 
Natural  Gas.  Geol.  Soc.  America  Butt.,  vol.  28,  p.  572,  1917. 


154 


GEOLOGY  OF  PETROLEUM 


the  movement  is  up  the  dip  the  accumulation  will  be  near  the  axis 
of  flexure,  where  the  dip  changes,  and  in  general  the  greatest 
accumulation  will  be  near  the  lower  edge  of  the  terrace  (Fig.  62). 
Such  conditions  exist  in  the  Peru  field,  in  southern  Kansas.  On 
the  other  hand,  if  little  water  is  associated  with  the  oil  it  tends 
to  move  downward,  and  accumulation  may  take  place  on  the  upper 
part  of  the  flat  limb  of  the  terrace.  These  relations  have  been 
shown  by  experiments  at  the  University  of  Minnesota  (see  p.  112). 


Pry  oil  sand 
Oil  accumulation 
Gas  accumulation 


FIG.  63. — Ideal  sketch  showing  accumulation  of  oil  and  gas  in  Appalachian 
region.  The  higher  sands  are  saturated  and  oil  and  gas  rises  to  crests  of  anti- 
clines. The  lower  sands  are  not  saturated  and  the  oil  and  gas  is  found  low  on 
the  flanks  of  the  anticlines  or  in  synclines.  (After  Griswold  and  Munn. ) 

RESERVOIRS  IN  SYNCLINES 

Oil  is  found  in  synclines  in  parts  of  the  Appalachian  region. 
In  the  Catskill  strata  in- Pennsylvania  and  West  Virginia  petroleum 
and  gas  are  found  in  sands  between  shales.  These  beds  are  not 
saturated  with  water.  Reeves1  states  that  these  unsaturated  beds, 
which  are  land  sediments,  had  dried  out  before  they  were  sub- 
merged in  the  sea  and  that  the  spaces  of  their  reservoirs  were  filled 
with  air.  Later  when  marine  sediments  were  laid  down  above 
them,  the  oil  evidently  migrated  into  them,  but  not  enough  water 
to  float  the  oil  to  the  tops  of  folds.  Some  of  the  Mississippian 
sands  above  the  Devonian  in  Pennsylvania  are  saturated,  and  in 

BEEVES,  FRANK:  The  Absence  of  Water  in  Certain  Sandstones  of  the 
Appalachian  Oil  Fields.  Econ.  Geology,  vol.  12,  pp.  254-278,,  1917. 


STRUCTURAL  FEATURES  OF  RESERVOIRS      155 


them  the  oil  and  gas  occur  in  anticlines, 
trated  by  Fig.  63. 

At  Urado,  Colorado, 
in  the  Uinta  Basin, 
near  the  Colorado  line, 
oil  has  been  produced 
from  a  tunnel  driven 
in  a  flat-lying  sand, 
the  base  of  which 
is  warped  to  form 
gentle  sags  in  which 
the  oil  collects.  Small 
amounts  of  oil  have 
been  obtained  also 
near  De  Beque,  in 
western  Colorado, 
from  wells  sunk  near 
the  axis  of  a  low  minor 
anticline  which  is  de- 
veloped in  a  broad 
syncline.  In  south- 
eastern Utah  a  little 
oil  has  been  found  in  a 
syncline  in  the  San 
Juan  field.  IntheMc- 
Kittrick  district,  Cali- 
fornia, a  considerable 
concentration  of  oil  is 
found  in  an  overturned 
syncline  (Fig.  64).  In 
Galicia  also  oil  is  found 
in  synclines  in  the 
Boryslaw  field. 

The  large  deposits 
of  oil  in  well-defined 
synclines  in  consoli- 
dated rocks  are  in  the 
Appalachian  field. 
Most  other  fields  in 
which  large  concentrations  are  found  in  synclines 


These  features  are  illus- 


are  in  unconsoli- 


156 


GEOLOGY  OF  PETROLEUM 


dated  rocks  that  have  been  intensely  deformed.  Under  such  con- 
ditions as  have  already  been  noted,  petroleum  is  apparently  found 
in  many  different  structural  positions. 

Some  synclines  are  merely  gentle  sags  near  the  crests  of  anti- 
clines. Such  sags  may  be  saturated  with  oil  or  gas  or  both  (Fig.  65). 
Others  contain  a  little  water  near  the  axis  of  the  sag..  In  still 
others  the  sand  may  be  filled  with  water. 

RESERVOIRS  FORMED  BY  FISSURES 

Practically  all  consolidated  rocks  are  jointed,  and  many  of  them 
are  appreciably  fractured.  The  earlier  investigators  of  oil  reser- 


^Cimarron  River 


.Sea  level 


-Oil  and  gas 


FIG.  65. — Section  of  Gushing  field,  Oklahoma,  showing  o'\\  in  a  synclinal  sag 
near  the  crest  of  an  anticline.  (After  Beal.) 

voirs  in  the  Appalachian  region  laid  much  emphasis  on  fissures  as 
containers  of  oil  and  gas.  Later,  when  great  fields  in  unconsol- 
idated  rocks  were  developed  in  Russia,  in  California,  and  elsewhere 
it  appeared  less  probable  that  fissures  play  so  important  a  part,  for 
in  soft  rocks  fissures  will  close.  -  The  effect  of  openings  formed  by 
solution,  dolomitization,  fracturing,  and  brecciation  has  been  men- 
tioned in  connection  with  the  discussion  of  reservoir  rocks.  Such 
openings1  doubtless  add  materially  to  the  capacity  of  reservoirs  in 
certain  fields  where  oil  occurs  in  Paleozoic  rocks.  In  the  uncon- 
solidated  rocks  of  some  Tertiary  fields  they  are  generally  less 
effective.  The  capacity  of  fissures  is  attested  by  those  that  are 
filled  with  bitumens — some  containing  many  millions  of  tons.  In 
some  fields  oil  is  recovered  from  fissures  in  shale. 

^AUER,  A.  W.:  Petrology  of  Reservoir  Rocks  and  Its  Influence  on  the 
Accumulation  of  Petroleum.  Econ.  Geology,  vol.  12,  pp.  435-465,  1917. 

LEWIS,  J.  O. :  (Discussion  of  LAUER'S  Paper).     Idem,  vol.  13,  pp.  65-69, 1918. 


STRUCTURAL  FEATURES  OF  RESERVOIRS       157 

At  Florence,  Colorado,  according  to  Washburne,1  the  principal 
reservoirs  are  fissures  in  the  shale  of  the  Pierre  formation.  This 
is  a  uniform  shale,  and  in  the  lower  part,  which  carries  the  petro- 
leum deposits,  no  sands  are  present.  The  fissured  area  is  in  a  great 
synclinal  basin,  the  Canyon  City  embayment,  and  the  fissures  are 
associated  with  small  flexures  and  faults.  The  oil  is  not  all  floated 
on  water,  although  some  salt  water  appears  in  some  of  the  deeper 
wells.  The  oil  is  associated  with  gas  under  pressure,  and  some  of 
the  wells  are  exploited  for  gas  alone.  The  oil  does  not  follow  any 
bed  or  series  of  beds  in  the  shale.  As  shown  by  the  outcrop,  the 
oil  zone  does  not  contain  any  sandstones  or  other  porous  beds 
capable  of  forming  reservoirs.  Evidence  that  the  oil  lies  in  joints 
and  fissures  consists  (a)  of  a  correspondence  in  direction  of  the 
major  joints  in  the  rocks  at  the  surface  with  the  alinement  of  wells 
which  have  interfered  with  one  another;  (b)  of  the  fact  that  many 
wells  have  been  drilled  within  a  few  feet  of  one  another  without 
encountering  oil  at  the  same  depth;  (c)  of  the  fact  that  gas  struck 
in  a  shallow  well  often  immediately  ruins  an  adjacent  well  several 
hundred  feet  deeper  by  tapping  the  source  of  pressure;  (d)  of  the 
fact  that  many  wells  drain  adjacent  wells  that  are  shallower^ 
(e)  of  the  indication  of  vertical  connection  between  the  oil  bodies 
shown  by  the  marked  increase  in  maximum  pressure  with  depth; 
and  (/)  of  the  dissimilar  pressures  in  adjacent  wells  of  the  same 
depth. 

In  the  Salt  Creek  field,  Wyoming,2  considerable  oil  has  been 
found  in  fissures  in  the  Cretaceous  shale.  This  region  is  a  domatic 
uplift  and  yields  oil  of  good  grade  from  the  Wall  Creek  sands  of 
the  Frontier  formation.  The  oil  in  the  sands  is  found  in  elevated 
portions  of  the  dome.  West  of  the  dome  there- is  a  great  syncline 
with  thick  shale  beds  in  which  the  oil  sands  carry  only  water.  In 
nearly  every  well  drilled  in  this  field,  according  to  Wegemann, 
some  oil  is  found  in  the  shale,  a  few  wells  having  an  initial  produc- 
tion of  as  much  as  1,500  barrels  a  day.  The  oil  is  not  obtained 
from  porous  beds  in  the  shale,  and  it  is  found  in  adjoining  wells  at 
different  depths.  The  shale  is  so  fine  grained  that  it  would  not  in 
itself  constitute  a  reservoir  for  oil,  as  the  openings  between  the 

'WASHBURNE,  C.  W. :  The  Florence  Oil  Field,  Colorado.  U.  S.  Geol.  Sur- 
vey Bull.  381,  pp.  517-544,  1910. 

2WEGEMANN,  C.  H.  \  The  Salt  Creek  Oil  Field,  Wyoming.  U.  S.  Geol. 
Survey  Bull.  670,  p.  36,  1917. 


158  GEOLOGY  OF  PETROLEUM 

particles  are  too  small  to  permit  oil  to  flow  rapidly  through  them. 
The  oil  from  the  Wall  Creek  sand  and  the  oil  from  shale  are  practi- 
cally identical,  the  only  difference  being  that  the  oil  from  the  sand 
contains  a  little  more  gas. 

The  shale  wells  start  flowing  under  considerable  pressure,  and 
fragments  of  calcite  are  often  ejected  from  the  wells.  The  calcite 
is  like  that  which  fills  or  partly  fills  the  fissures  in  the  shale.  Pre- 
sumably the  oil  is  derived  from  the  Wall  Creek  sand  below.  Cer- 
tain of  the  faults  in  the  shale  extend  down  to  the  sand  and  afford 
passages  through  which  the  oil  in  the  sand,  under  great  pressure, 
has  been  forced  upward  into  the  shate.  As  the  fissures  in  the 
shale  are  not  confined  to  the  dome  itself  but  extend  into  the  adjoin- 
ing syncline  on  the  west,  oil  has  been  forced  laterally  through  the 
fissures  into  the  shale  of  the  syncline.  The  Wall  Creek  sand, 
wherever  it  has  been  reached  in  this  synclinal  area,  has  pro- 
duced water. 

Shales  that  yield  oil  also  yield  gas.  In  some  regions  gas  only  is 
obtained  from  the  shale  reservoirs.  In  Cleveland,  Ohio,1  and  in 
the  surrounding  country  wells  have  been  sunk  in  the  shale  for 
domestic  supply.  As  a  rule  the  pressure  is  low  and  the  yield  small, 
but  the  wells  have  long  life,  so  that  farmers  find  the  fuel  suitable 
for  domestic  use.  Some  wells  supply  one  or  two  farm  houses. 

Orton,2  describing  the  differences  between  shale  gas  and  "reser- 
voir gas,"  notes  that: 

Shale-gas  wells  are  generally  of  small  volume,  compared  to  wells 
deriving  their  gas  from  sand  reservoirs.  Moreover  they  lack  uni- 
formity of  rock  pressure.  Wells  drilled  in  close  proximity  and  to 
the  same  depth  may  have  very  different  pressures.  In  sand  reser- 
voirs, pressures  are  generally  greater  and  more  nearly  uniform. 
In  the  wells  yielding  shale  gas  there  is  no  definite  horizon  from 
which  their  gas  supply  is  derived.  The  stratum  that  yields  it  may 
be  several  hundred  feet  thick,  and  gas  is  likely  to  be  found  at  any 
point  in  the  descent.  Shale-gas  wells,  though  in  the  same  field, 
may  be  expected  to  show  a  considerable  range  in  depth.  Some 
shale-gas  wells  occur  independently  of  oil  production.  Gas  may 
be  abundant,  while  petroleum  is  altogether  wanting.  Shale-gas 

*VAN  HORN,  F.  R. :  Reservoir  Gas  and  Oil  in  the  Vicinity  of  Cleveland,  Ohio. 
Amer.  Inst.  Min.  Eng.  Bull.  121,  pp.  75-86,  1917. 

2ORTON,  EDWARD:  Geological  survey  of  the  lola  Gas  Field.  Geol.  Soc, 
America  Bull,  vol.  10,  p.  100,  1899, 


STRUCTURAL  FEATURES  OF  RESERVOIRS     159 

wells  are  long  lived.  Weak  flows  are  maintained  for  long  periods. 
Shale  gas  is  not  dependent  on  the  structural  arrangement  of  the 
rocks  which  contain  it.  If  it  is  not  associated  with  oil  or  water,  it 
can  not  be  displaced  nor  crowded  out  by  them. 

ACCUMULATION  IN  SANDS  OF  IRREGULAR  PORE  SPACE 

In  many  oil  fields  the  oil-producing  sands  are  irregular  or 
"spotted."     Borings  that  yield  neither  oil,  gas  nor  water  may  be 


FIG.  66. — Sketch  contour  map  showing  accumulations  of  oil  and  gas  in 
sands  that  are  only  locally  pervious. 

sunk  in  a  sand  that  contains  oil  or  gas  on  all  sides  of  it.     Examina- 
tion of  fragments  of  the  oil  stratum  in  the  boring  may  discover  a 
tight  sand  in  which  the  pore  space  is  filled  by  calcite,  pyrite  or 
other  secondary  minerals,  or  one  that  is  filled  with  clay. 
On  many  domes  and  anticlines,  as  already  noted,  a  belt  that 


160 


GEOLOGY  OF  PETROLEUM 


yields  oil  is  found  below  a  disk  of  gas-filled  sand.  Some  wells, 
however,  that  are  sunk  in  the  oil-producing  belt  may  yield  gas 
only.  Examination  may  reveal  a  sand  that  is  coarser  grained  and 
contains  larger  pores  than  the  sands  elsewhere  in  the  oil-bearing 
area,  for  in  some  fields,  gas  tends  to  accumulate  in  the  larger 
openings.  Irregular  and  fantastic  patterns  of  areas  of  produc- 
tion are  displayed  in  pools  containing  "spotted"  sands.  Neverthe- 
less, in  the  areas  of  porous  rock  that  are  surrounded  by  impervious 
rocks  at  the  same  horizon,  the  oil,  gas,  and  water  that  are  con- 
contained  in  the  porous  rock  are  generally  segregated  in  belts,  the 
gas  above  the  oil  and  the  water  below  it,  as  is  illustrated  by  Fig. 
66.  In  such  a  field  where  pools  are  not  connected  by  open  spaces 


Afroston  Surfaces          ..—-rOiland gas 


.  -  -">:5<*tt  wo/rer. 


Jcmoiy  shale 


Oilomdgas 


Salt-  water 


FIG.  67. — Ideal  sketch  through  a  dome,  showing  accumulations  of  oil  and  gas 
in  sand-filled  channels,  and  directions  of  migration.  (After  Wallace  Lee.) 

in  the  petroliferous  stratum  the  lines  of  .contact  between  gas  and 
oil  and  between  oil  and  water  may  be  found  at  widely  different 
elevations. 

ACCUMULATIONS  AT  UNCONFORMITIES 

Unconformities  are  favorable  places  for  the  accumulation  of  oil 
and  gas  because  the  material  laid  down  first  along  an  advancing 
shore  line  is  generally  coarse.  The  strata  formed  at  the  bottom 
of  a  sedimentary  series  generally  contain  conglomerate  and  coarse 
sand.  As  a  rule,  such  material  has  been  washed  over  by  waves 
and  the  fine  clay  has  been  removed  from  it.  Thus  the  basal  beds 
are  likely  to  contain  many  large  openings  suitable  for  the  accumu- 
lation of  oil  and  gas.  At  some  unconformities  the  surface  on  which 
the  upper  series  was  laid  down  is  irregular,  and  the  porous  beds  are 
likely  to  be  distributed  as  small  lenses.  Thus  the  reservoirs 
formed  by  such  rocks  will  be  spotted.  When  such  a  reservoir  is 


STRUCTURAL  FEATURES  OF  RESERVOIRS    161 

thrown  into  folds  the  oil  and  gas  will  accumulate  at  the  crests  of 
the  folds  where  the  lenses  of  porous  rock  lie  at  the  crests  and  in  the 
upper  parts  of  the  lenses  that  lie  on  the  flanks  of  the  folds  (Fig.  67). 
In  the  Colmar  district,  Illinois,  oil  and  gas  are  found  in  the  Hoing 
sand,  at  the  base  of  the  Niagara,  which  lies  unconformably  on  the 
Maquoketa  shale  at  places  where  it  is  locally  developed. 

Among  the  examples  of  reservoirs  at  unconformities  are  those 
of  the  McKittrick-Sunset  district,  California,  where  large  accu- 
mulations are  foundatthebaseoftheMcKittrickbeds,whichoverlie 
older  rocks  unconformably.  In  the  Coalinga  district,  California, 
oil-bearing  beds  are  found  at  three  unconformities.  Some  other 
examples  of  accumulation  at  unconformities  are  mentioned  on 

pages  149-151. 

SUCCESSIONS  OF  PETROLIFEROUS  STRATA 

Oil  reservoirs  are  almost  invariably  related  to  geologic  structure* 
There  is  no  better  proof  of  this  relation  than  the  accumulation  of 
oil  in  different  beds,  one  below  the  other,  in  the  same  field,  and  the 
absence  of  oil  in  commercial  accumulations  in  the  surrounding 
regions. 

In  many  pools  oil  is  found  in  more  than  one  stratum.  In  some 
it  is  found  in  five  strata  or  more.  Where  the  structure  is  anti- 
clinal and  there  is  an  accumulation  of  petroleum  in  the  upper  sand 
at  the  crest,  it  is  reasonable  to  suppose  that  lower  strata,  if  con- 
formable, lie  in  anticlines  also,  and  that  if  they  are  porous  they 
may  contain  additional  reserves.  In  some  districts  the  amplitude 
of  folds  increases  with  depth,  and  deeper  accumulations,  situated 
on  the  greater  folds,  are  more  productive  than  the  shallow  pools. 
Many  fields  have  been  revived  again  and  again  by  deeper  drilling. 

Where  petroliferous  beds  are  steeply  folded,  as  they  are  in  the 
Grozny  field,  north  of  the  Caucasus  Range,  Russia;  in  the  Yenang- 
yat-Singu  field,  Burma;  and  in  other  fields  that  contain  accumula- 
tions of  oil  in  Mesozoic  and  Tertiary  rocks,  where  successive  oil 
strata  have  been  discovered,  the  planes  that  pass  through  the 
crests  of  folds  or  the  "crest  loci,"  are  not  vertical  but  dip  at  high 
angles.  In  general,  if  not  invariably,  the  crest  locus  will  dip 
toward  the  gentle  limb  of  an  asymmetric  fold,  and  accumulation 
on  the  gentle  side  of  the  fold  as  shown  at  or  near  the  surface  will  be 
even  more  pronounced  in  depth. 

In  oil  fields  on  monoclines  regular  successions  of  petroliferous 


162  GEOLOGY  OF  PETROLEUM 

strata  are  less  likely  to  be  discovered  than  on  domes.  Neverthe- 
less, such  series  have  been  found  at  many  places.  Even  some 
monoclinal  traps  that  are  formed  by  the  porous  sands  tightening 
up  the  dip,  either  by  changing  to  clayey  strata  or  by  cementation 
of  porous  sands,  have  been  found  to  contain  several  accumula- 
tions, one  below  another.  Sands  wedge  out  away  from  shore  lines, 
and  many  sands,  one  below  another,  may  be  related  to  the  same 
shore  line.  Faults  that  bring  impervious  strata  against  sands  and 
thus  seal  reservoirs  may  cross  a  series  of  sands  providing  condi- 
tions for  accumulation  at  several  horizons.  Dikes  or  other  intru- 
sive bodies  that  seal  one  member  of  a  petroliferous  series  are  likely 
to  seal  others. 

In  oil  fields,  on  terraces  more  than  one  petroliferous  bed  may  be 
found.  Obviously,  if  the  rate  of  dip  changes  in  the  higher  beds,  it 
will  generally  change  also  in  the  lower  beds. 

DISTANCES  COVERED  IN  THE  MIGRATION  OF  PETROLEUM 

In  some  regions  there  is  evidence  that  petroleum  has  migrated 
considerable  distances.  /  In  Wyoming,  where  the  dips  are  high, 
essentially  all  the  petroleum  recovered  is  found  in  small  sharp 
domes  or  other  uplifts.  The  gathering  grounds  are  very  large 
compared  with  the  areas  of  accumulation.  Some  of  the  oil  has 
probably  moved  several  miles,  perhaps  a  score  of  miles  or  more, 
to  accumulate  in  the  high  structural  positions.  In  this  and  other 
regions  the  contact  with  the  salt  water  that  lies  below  the  oil — 
that  is,  the  "edge  water" — is  not  a  level  line  but  descends  to 
lower  levels  on  the  side  toward  which  the  gathering  ground  is 
greatest.  In  the  Salt  Creek  dome  the  base  of  the  conical  oil 
blanket  descends  about  100  feet  on  the  northeast  side,  toward  the 
great  syncline  that  lies  between  the  Big  Horn  Mountains  and  the 
Black  Hills.  In  the  Gushing  field,  Oklahoma,  the  oil  descends  to 
greater  depths  down  the  west  side  of  the  dome,  which  lies  toward 
the  basin,  than  it  does  on  the  east.  In  Lambton  County,  Ontario, 
there  are  noteworthy  descents  of  the  oil-saturated  rocks  of  each  of 
the  great  pools,  and  accumulations  are  greatest  toward  the  areas 
where  the  gathering  ground  is  greatest.  On  the  Volcano  anti- 
cline, West  Virginia,  the  accumulation  is  concentrated  on  the  west 
side  of  thfc  axis.  In  these  and  many  other  regions  the  positions 
of  the  most  productive  sides  of  the  domes  with  respect  to  the 
greatest  gathering  areas  indicate  clearly  that  migration  of  petro- 


STRUCTURAL  FEATURES  OF  RESERVOIRS    163 

leum  has  been  greatest  where  the  area  from  which  supplies  could 
have  come  is  greatest. 

In  many  regions  minor  anticlines  or  domes  are  found  one  below 
another  down  the  dip  on  great  monoclines  that  slope  away  from 
mountain  uplifts.  The  greatest  accumulations  are  commonly  on 
the  lower  folds — that  is,  on  those  that  lie  on  the  basinward  side — 
which  in  general  have  greater  gathering  grounds  than  folds  higher 
on  the  monocline.  These  relations  are  clearly  shown  in  the  Big 
Horn  Basin,  Wyoming, 1  and  at  many  other  places. 

Some  accumulations  are  so  great  that  the  inference  is  warranted 
that  they  are  drawn  from  large  areas.  In  the  famous  Baku  oil 
field  of  Russia  accumulations  that  cover  small  areas  are  very  large. 
More  than  one-tenth  of  the  world's  production  of  petroleum  has 
been  derived  from  an  area  of  less  than  3,000  acres  in  the  Balak- 
hany-Sabunchy-Romany  field.  It  is  improbable  that  such  large 
accumulations  could  form  only  from  strata  near  them.  The  oil 
doubtless  has  moved  great  distances  to  collect  in  the  structurally 
favorable  areas. 

These  observations  tend  to  confirm  the  conclusion  that  oil  has 
migrated  considerable  distances  in  some  districts.  In  northeastern 
Oklahoma,  where  the  domes  and  anticlines  are  flat  and  closely 
spaced  and  saturation  is  high,  the  oil  pools  are  near  together, 
especially  in  the  area  east  of  Bartlesville,  in  Osage,  Washington, 
and  Nowata  Counties.  In  this  area  the  oil  has  probably  migrated 
shorter  distances.  More  definite  statements  are  not  warranted. 
An  extreme  view  is  expressed  by  McCoy,2  who  believes  that  the 
oil  of  this  area  has  been  derived  from  materials  near  at  hand  and 
has  entered  the  oil  reservoirs  themselves  along  faults  connecting 
the  sands  and  the  shales.  It  is  believed  by  Van  Verveke  that 
the  petroleum  of  the  Alsace  field  originated  near  the  reservoirs 
that  contain  it. 

MINIMUM  INCLINATION  NECESSARY  FOR  MIGRATION 

The  inclination  necessary  for  migration  varies  with  the  porosity 
and  size  of  pores,  gas  pressure,  and  viscosity  of  the  oil.  Examples 
are  not  rare  where  segregation  has  taken  place  in  sands  dipping  less 

^IEWETT,  D.  F.,  and  LUPTON,  C.  T. :  Anticlines  in  the  Southern  Part  of  the 
Big  Horn  Basin,  Wyoming.     U.  S.  Geol.  Survey  Bull  656,  p.  44,  1917. 

2McCoY,  A.  W. :  Notes  on  Principles  of  Oil  Accumulation.  Jour.  Geology, 
vol.  27,  p.  254,  1919. 


164 


GEOLOGY  OF  PETROLEUM 


than  half  a  degree.  In  the  Lambton  County  field,  Ontario,  where 
the  oil  is  found  in  a  porous  limestone,  the  segregation  in  pools  at 
crests  of  folds  is  very  clear.  The  beds  in  general  dip  less  than  50 
feet  to  the  mile,  and  at  many  places  the  dips  are  much  lower.  In 
the  Mid-Continent  field,  migration  has  probably  taken  place  in 
beds  dipping  less  than  20  feet  to  the  mile.  -Laboratory  experi- 


^\          /cr\          /^\         /—N 


FIG.  68. — Sketches  illustrating  (a)  ideal  parallel,  and  (6)  ideal  similar  folds. 

(After  Van  tfise.) 

ments  at  the  University  of  Minnesota  (p.  110)  show  that  oil  will 
move  very  readily  through  sands  in  tubes  tilted  less  than  one  de- 
gree, when  gas  is  present  under  low  pressure  in  a  closed  system. 

BEHAVIOR  OF  FOLDS  IN  DEPTH 

The  zone  of  deformation  affected  by  mountain-forming  folds  is 
comparatively  shallow.  Thus,  in  the  region  between  Tyrone  and 
Harrisburg,  Pennsylvania,  the  depth  involved  as  calculated  by 


STRUCTURAL  FEATURES  OF  RESERVOIRS     165 

R.  T.  Chamberlin1  is  estimated  to  be  5.7  miles  at  one  end  of  an 
earth  element  and  32.7  miles  in  the  region  affected  at  greatest 
depth. 

In  areas  of  deformation  two  types  of  folding  are  distinguished. 
In  one  type  the  beds  are  approximately  parallel  throughout. 
Such  folds  are  known  as  parallel  folds  (Fig.  68,  a).  In  the  other 
type  the  curvatures  of  the  beds  tend  to  remain  the  same.  In 
readjustment  of  beds  to  fit  the  fold,  all  parts  of  the  bed  are  affected. 
Such  folds  are  known  as  similar  folds  (Fig.  68,  b).  Similar  folds 
are  characteristic  of  deformation  at  great  depths,  where  beds  are 
folded  in  the  zone  of  flowage.  Folding  of  this  type  is  exhibited  in 
the  Vermilion  iron  range,  in  the  Marquette  iron-bearing  district, 
and  at  many  other  places  in  the  Lake  Superior  region,  where  it  has 
been  investigated  by  Van  Hise,2  Leith,3  and  others. 

In  areas  of  similar  folding  the  folds  persist  vertically  and  may 
remain  similar  through  great  depths.  In  areas  of  parallel  folding 
the  deformation  is  less  intense  and  the  amplitude  of  the  folds  is 
likely  to  change  with  depthv  The  highest  bed  represented  in  Fig. 
68a,  shows  folds  of  very  low  amplitude;  the  amplitudes  of  the 
folds  in  the  lower  beds  become  greater  but  finally  decrease  again. 
This  is  the  type  of  folding  which  is  characteristic  of  many  petrolif- 
erous areas  in  rocks  older  than  the  Mesozoic.  In  such  areas,  there- 
fore, the  amplitude  of  folds  may  be  expected  to  increase  in  depth 
where  erosion  has  not  removed  the  higher  parts  of  the  folded  zone, 
exposing  conditions  illustrated  in  the  lower  part  of  Fig.  68a. 

Where  only  one  fold  is  developed  such  a  fold  also  may  become 
sharper  with  depth./  The  conditions  are  illustrated  by  Fig.  69, 
which  represents  an  experiment  by  Willis. 4  The  fold  was  produced 
by  force  applied  at  the  right  end.  The  anticline  shown  in  the  lower 
sketch  is  sharper  in  the  lower  beds. 

Pressure  applied  horizontally  to  bodies  of  strata  is  frequently 

CHAMBERLIN,  R.  T. :  Appalachian  Folds  of  Central  Pennsylvania.  Jour. 
Geology,  vol.  18,  pp.  228-251,  1910. 

2VAN  HISE,  C.  R.,  and  LEITH,  C.  K. :  Geology  of  the  Lake  Superior  Region. 
U.  S.  Geol.  Survey  Mon.  52,  p.  123,  1911. 

VAN  HISE,  C.  R. :  Principles  of  North  American  Pre-Cambrian  Geology. 
U.  S.  Geol.  Survey  Sixteenth  Ann.  Rept.,  part  1,  pp.  597-601,  1895. 

3LEiTH,  C.  K. :  Structural  Geology.  P.  107,  New  York,  Henry  Holt  &  Co., 
1913. 

4  WILLIS,  BAILE.Y  :  Mechanics  of  Appalachian  Structure.  U.  S.  Geol.  Survey 
Thirteenth  Ann.  Rept.,  part  2,  p.  247,  1893. 


166 


GEOLOGY  OF  PETROLEUM 


relieved  by  faulting.  The  stresses  are  applied  at  considerable 
depths  but  are  relieved  upward  because  the  rock  bodies  can  most 
readily  move  upward.  Frequently  the  stresses  are  relieved  along 
an  inclined  plane,  as  is  illustrated  by  Fig.  70.  If  the  upper  strata 
include  shales  or  clays,  as  is  common  in  oil  fields,  the  upthrust  is 


FIG.  69. — Sketches  showing  deformation  of  beds  by  lateral  pressure.  (After 

Willis.) 


partly  taken  up  by  compacting  the  shales.  Thus  in  areas  of  rel- 
atively gentle  deformation  the  fold  originating  in  depth  may  tend 
to  die  out  toward  the  surface. 

In  many  oil  fields  of  the  earth  the  amplitudes  of  folds  increase 


STRUCTURAL  FEATURES  OF  RESERVOIRS    167 

with  depth.  That  is  true  in  certain  European  fields  where  folding 
occurred  between  the  periods  of  deposition  of  the  several  petrolif- 
erous series./  It  is  illustrated  in  Rumania,  where  folding  and 
deposition  of  strata  that  yield  petroleum  took  place  alternately 
through  a  long  period  in  Miocene  time.  In  the  Oklahoma-Kansas 
field  the  increase  in  amplitude  of  folds  with  depth  has  been  noted 
by  many  investigators.  In  northern  Texas  some  very  gentle  half 
domes  become  closed  with  depth.  In  some  folded  areas  the  ampli- 
tudes of  folds  increase  with  depth  because  the  lower  beds  were 


FIG.  70. — Sketch  showing  folds  developed  above  a  fault. 

folded  before  the  upper  ones  were  laid  down  unconformably  over 
them. 

The  increase  of  folding  with  depth  is  illustrated  in  the  Gushing 
pool,  Oklahoma.  Fig.  71  shows  contours  on  the  out-cropping 
Pawhuska  limestone  as  mapped  by  Buttram.  These  contours 
indicate  folds  of  small  amplitude.  The  contours  on  the  Bartles- 
ville  sand  as  mapped  by  Conkling 1  indicate  folds  of  much  greater 
amplitude  (Fig.  72).  As  shown  by  the  cross  section  along  the  north 
line  of  Sees.  8  and  9  (Fig.  73),  the  Tucker  sand  dips  much  more 
steeply  than  the  Bartlesville  sand.  The  shale  between  the  Bartles- 

^ONKLING,  R.  A. :  The  Influence  of  the  Movement  in  Shales  on  the  Area  of 
Oil  Production.  Am.  Inst.  Min.  Eng.  B-uJl.  119,  pp.  1969-1972,  1916. 


168 


GEOLOGY  OF  PETROLEUM 


ville  and  the  Tucker  becomes  thinner  at  the  crest  of  the  anticline. 
Ohern1  states  that  there  is  probably  an  unconformity  below  the 
Bartles ville  sand  in  the  Gushing  region. 

In  Oklahoma,  northern  Texas,  and  Louisiana,  gentle  deforma- 
tion has  been  going  on  until  a  very  late  geologic  period,  continuing, 
locally  at  least,  well  into  the  Tertiary,  if  not  to  recent  times.  It  is 
obvious  that,  for  the  parts  of  this  region  where  parallel  folds  have 


R  7  E 


FIG.  71. — Sketch  showing  part  of  Gushing  field,  Oklahoma,  with  contours  on 
Pawhuska  limestone.   (After  Buttram.) 

formed  and  where  erosion  has  not  cut  too  deep  into  the  deformed 
zone,  the  present  surface  is  in  the  upper  part  of  the  deformed  ele- 
ment, as  illustrated  in  Fig.  68a,  and  that  an  increase  of  ampli- 
tude of  folds  with  depth  may  be  expected. 

It  is  noteworthy  that  in  the  lower  part  of  Fig.  68a  the  ampli- 
tudes of  the  upward  folds  decrease  with  depth.  Toward  the  axes 

^HERN,  D.  W.:  The  Influence  of  the  Movement  in  Shales  on  the  Area  of 
Oil  Production  (Discussion  of  Paper  by  RICHARD  A.  CONKLING,  New  York 
Meeting,  Feb.,  1917).  Am.  Inst.  Min.  Eng.  Bull  123,  pp.  389-390,  1917. 


STRUCTURAL  FEATURES  OF  RESERVOIRS    169 


FIG.  72. — Sketch  showing  part  of  Gushing  field,  Oklahoma,  with  contours 
on  Bartlesville  sand.     Contour  interval  is  ten  feet.     (After  Conkling. ) 

of  these  folds  the  dip  increases.  Stigand1  states  that  when  the  dips 
increase  toward  an  anticlinal  axis  on  both  sides,  such  anticlines 
"can  rarely  give  good  results.7'  Such  anticlines,  he  states,  are 
found  in  Crimea. 


1650- 
1675- 

noo- 
nes- 

1750- 


1800- 


1850- 
1875- 


1900-^ 
1925- 

1950 d- 

J 


-BarHasville 


'Tucker 


Vertical  Scale  ^>u&h 


1 


FIG.  73.— Section  showing  top  of  Bartlesville  and  Tucker  sands  in  part  of 
Gushing  field,  Oklahoma.  The  interval  between  the  sands  increases  away 
from  the  crest  of  the  anticline.  (After  Conkling.} 


,  I.  A. :  Discussion  of  a  Paper  by  THOMPSON  in  Inst  Min.  and  Met. 
Trans.,  vol.  20,  p.  264,  London,  1911. 


CHAPTER  XI 
DEFORMATION  OF  PETROLIFEROUS  STRATA 

Deformation  in  Unconsolidated  Materials.— In  many  districts 
the  petroliferous  beds  are  covered  by  strata  that  include  consider- 
able thicknesses  of  unconsolidated  clay,  marl,  or  clayey  sand.  IP 
such  districts,  even  after  extensive  deformation  by  folding  and 
faulting,  the  reservoir  rocks  may  retain  large  accumulations  of  oil 
and  gas.  ^  Some  of  the  most  productive  oil  fields  are  in  areas  of 
rocks  that  are  largely  unconsolidated  where  the  beds  lie  in  over- 
turned folds  or  are  greatly  disturbed  by  complicated  faults.  In 
unconsolidated  materials  openings  due  to  faulting  and  folding  tend 
to  close  promptly,  so  that  the  oil  remains  in  the  reservoir.  In 
such  materials  there  is  generally  some  leakage,  however,  and  oil 
seeps,  asphalt,  gas  seeps,  mud  volcanoes,  brine  springs,  and  other 
surface  associates  of  oil  or  gas  are  generally  found  above  the 
reservoirs.  Many  of  the  Tertiary  oil  fields  are  in  highly  deformed 
rocks.  These  include  many  districts  in  Galicia,  Rumania,  Russia, 
Burma,  Java  and  other  fields  of  Oceanica,  and  the  principal  fields 
of  California.  These  fields  in  general  are  marked  by  prominent 
surface  indications  of  oil,  and  most  of  them  are  in  areas  of  com- 
plicated faulting  or  folding.  In  consolidated  rocks  that  had 
undergone  so  much  deformation  the  gas  pressure  would  have 
driven  the  bulk  of  the  available  oil  from  its  reservoirs.  In  con- 
solidated rocks  the  most  productive  fields  are  found  in  regions  that 
have  suffered  only  gentle  deformation.  Oil  reservoirs  in  consol- 
idated rocks  have  doubtless  lost  their  stores  by  leakage  attending 
thrust  faulting  and  overturned  folding.  In  consolidated  rocks  oil 
generally  is  in  the  simpler  structural  features  only;  in  unconsoli- 
dated rocks  it  is  often  found  in  the  most  complicated  ones,  as  is 
shown  in  many  fields  in  California,  Galicia  and  Rumania.  In 
some  of  these  fields  folding  probably  took  place  after  accumula- 
tion. In  such  strata  the  oil  may  be  found  in  synclines  or  in  any 
other  position  with  regard  to  the  structure. 

Influence  of  Faulting  on  Reservoirs. — The  shales  that  supply  the 
so-called  impervious  covers  to  keep  the  petroleum  confined  within 
the  sandstones  are  not  absolutely  impervious  to  fluids,  otherwise 
the  oil  and  gas  could  not  pass  from  them  to  the  porous  beds  in 

170 


DEFORM  A  TION  OF  PETROLIFERO  US  STRA  TA     171 

which  they  are  found.  Fracturing  doubtless  facilitates  the  pas- 
sage, however,  by  supplying  more  readily  available  openings.  In 
the  Santa  Clara,  Summerland,  Puente  Hills,  Los  Angeles,  and  other 
California  districts  the  fracturing  appears  to  have  aided  accumu- 
lation by  permitting  the  oil  to  move  from  lower  to  higher  levels, 
where  it  is,  of  course,  more  readily  accessible.  The  oil  accumula- 
tion in  the  dome  near  Jennings,  Louisiana,  is  said  to  be  related  to  a 
fault.  In  the  Labarge  and  Spring  Valley  regions,  Wyoming,  the 
oil  seeps  are  obviously  related  to  planes  of  movement  subsidiary 
to  the  great  Absaroka  fault.  In  the  Brunswick  district,  Okla- 
homa, several  quarries  of  bituminous  rock  are  opened  on  or  near 
normal  faults.1  Other  asphalt  and  ozokerite  deposits  in  fissures 
have  been  mentioned.  It  is  clear  that  some  faults  have  served  as 
channels  through  which  petroleum  has  moved. 

As  is  well  known  by  students  of  ore  deposits  the  fissures  that 
serve  as  channels  of  metalliferous  waters  and  the  openings  that  are 
filled  by  metalliferous  ores  are  in  general  the  fissures  and  faults  of 
small  throw  rather  than  the  great  faults.  Except  in  limestone  a 
comparatively  small  number  of  veins  are  formed  in  faults  of  con- 
siderable tangential  movement.  Without  doubt  the  gouge  devel- 
oped along  the  greater  faults  provides  an  impermeable  barrier  and 
prevents  circulation.  It  is  obvious  that  this  principle  will  apply 
also  in  many  districts  that  yield  petroleum.  •  The  smaller  faults 
may  serve  as  channels  for  migration  and  escape  of  oil,  whereas  the 
greater  faults  may  seal  the  reservoirs. 

In  many  oil  fields  the  beds  are  cut  by  faults  along  which  neither 
asphalt  nor  oil  seeps  have  been  observed.  In  the  Lander  field, 
Wyoming,  oil  seeps  and  tar  springs  are  found  at  the  surface,  but 
along  a  thrust  fault  over  2  miles  long,  with  a  throw  of  1,180  feet, 
that  penetrates  the  Little  Popo  Agie  dome,  neither  oil  seeps  nor 
asphalt  deposits  were  noted,  although  the  oil  flows  from  some  of 
the  wells  and  is  under  pressure. 2 

The  Irvine  oil  field,  Kentucky,  lies  along  a  fault,  as  do  also  the 
Homer  and  Gusher  Bend  fields,  Louisiana.  According  to  McCoy 

^LDRIDGE,  G.  H.:  The  Asphalt  and  Bituminous  Rock  Deposits  of  the 
United  States.  U.  S.  Geol.  Survey  Twenty-second  Ann.  Rept.,  part  1,  p.  306, 
1901. 

WOODRUFF,  E.  G. :  The  Lander  Oil  Field,  Fremont  County,  Wyoming. 
U.  S.  Geol.  Survey  Bull  452,  1911. 


172  GEOLOGY  OF  PETROLEUM 

small  faults  are  present  in  many  of  the  Oklahoma  fields  and  appar- 
ently influence  accumulation  favorably. 

In  the  southern  California  districts  many  strong  faults  cut 
the  oil-bearing  strata,  but  relatively  few  of  these  are  marked  by 
great  oil  seeps  and  asphalts.  In  the  Santa  Cruz  district1  the 
Thurber,  New,  and  Hole  bituminous  sandstone  quarries  are  on 
faults,  as  is  also  a  prominent  brea  deposit  in  the  Los  Angeles  dis- 
trict. Considering,  however,  the  large  amount  of  oil  and  of  asphalt 
and  bituminous  rock  in  California,  and  the  large  number  of  faults 
that  occur  in  the  oil  fields,  the  number  of  faults  that  carry  large 
deposits  of  the  natural  hydrocarbons  is  small. 

The  Buckhorn  district,  Oklahoma,  contains  numerous  faults 
and  numerous  areas  of  bituminous  rock,  yet  there  is  no  very 
obvious  relation  of  some  of  the  deposits  of  the  bituminous  rock  to 
the  greater  fault  planes.2  In  the  Uinta  Basin,  Utah  and  Colorado, 
the  gilsonite  veins,  though  remarkably  uniform  as  to  strike,  ap- 
parently occupy  fissures  of  little  or  no  displacement,3  and  so  also 
do  the  wurtzilite  veins  in  the  Uinta  district.  The  grahamite  vein 
in  Ritchie  County,  West  Virginia,  occupies  a  fissure  along  which 
very  little  if  any  displacement  by  faulting  has  been  shown. 4 

^LDRIDGE,  G.  H.:  Op.  cit.y  p.  393. 

2ELDRiDGE,  G.  H.:  Op.  tit.,  p.  274. 

*Idem,  p.  339. 

4WniTE,  I.  C.:  Origin  of  Grahamite.  Geol.  Soc.  America  Bull.,  vol.  10,  p. 
278,  1898. 

ELDRIDGE,  G.  H.:  Op.  cit.t  p.  232. 


CHAPTER  XII 

METAMORPHISM  OF  PETROLEUM  BY  DYNAMIC 
AGENCIES 

Petroleums  and  the  materials  of  which  they  are  formed  are 
changed  by  the  heat  and  pressure  that  attend  dynamic  metamor- 
phism  of  strata.  In  the  Appalachian  region  and  in  the  Mid-Con- 
tinent field  of  the  United  States  petroleum  and  gas  are  closely 
associated  geographically  with  beds  containing  coals,  and  the 
degree  of  metamorphism  of  the  coals  affords  a  kind  of  index  to  the 
intensity  of  the  metamorphic  processes.  In  these  regions  the  coals 
are  altered  progressively  more  toward  the  areas  of  intense  deforma- 
tion. The  hydro-carbons  are  driven  off  and  the  coal  becomes 
richer  in  fixed  carbon.  In  the  Appalachian  region  the  amount  of 
fixed  carbon  is  greater  in  the  most  highly  folded  area  and  decreases 
toward  the  west,  where  the  intensity  of  metamorphism  is  de- 
creased. Petroleum  and  gas  in  reservoirs  associated  with  the  coals 
show  differences  corresponding  to  the  alteration  of  the  coals.  This 
relation  between  the  distribution  of  oil  and  the  character  of  coal 
was  first  shown  by  David  White1  and  has  been  treated  also  by 
Fuller2  and  by  Gardner.3 

In  the  Appalachian  region,  as  stated  by  Fuller,  neither  oil  nor 
gas,  except  in  a  few  minor  accumulations,  has  been  found  east  of 
the  west  face  of  the  outermost  strong  fold  of  the  Appalachian 
Mountains  (Fig.  74).  Between  this  face  and  the  line  of  60  per 
cent  carbon  coals  there  is  much  gas  in  the  northern  part  of  the 
field  and  some  in  the  southern  part,  with  an  oil  pool  here  and  there, 
but  the  main  oil  field  is  west  of  the  60  per  cent  carbon  line.  (See 
Fig.  75.) 

In  the  Ouachita-Arbuckle  region,  Oklahoma  and  Arkansas, 
according  to  Gardner,  gas  only  has  been  found  in  the  region  near 
and  northwest  of  the  Choctaw  fault.  The  main  oil  fields  are  50 

^HITE,  DAVID:  Some  Relations  in  Origin  Between  Coal  and  Petroleum. 
Washington  Acad.  Sci.  Jour.,  vol.  5,  pp.  189-212,  1915. 

2FuLLER,  M.  L.:  Appalachian  Oil  Fields.  Geol.  Soc.  America  Bull.,  vol. 
28,  p.  643,  1917. 

GARDNER,  J.  H. :  The  Mid-Continent  Oil  Field.  Geol.  Soc.  America  Bull., 
vol.  28,  pp.  685-720,  1917. 

173 


174  GEOLOGY  OF  PETROLEUM 

miles  or  more  northwest  of  the  Choctaw  fault,  although  there  are 
10  or  more  gas  fields  in  this  region. 

Fig.  76  is  a  map  showing  isovols1  in  Oklahoma,  according  to 
Fuller.2      The  maximum    production   has   come  from  the  zone 


FIG  74  — Map  of  Appalachian  region,  showing  relation  of  developed  oil  fields 
to  the  line  of  60%  fixed  carbon  in  coals.   (After  Fuller.) 

between  the  50  and  55  isovols.     Fuller  states  that  the  promise  of 
the  various  zones  is  roughly  as  stated  below : 

Relative  Chances  of 
Finding  Oil 

Zone  of  50%  to  55%'  carbon  ratios 100 

Zone  of  55%  to  60%  carbon  ratios 10 

Zone  of  60%  to  65%  carbon  ratios 1 

*An  isovol  is  a  line  connecting  points  where  the  coals  have  equal  percentages 
-of  fixed  carbon  (and  therefore  of  volatile  matter).  See  White,  David,  Wash- 
ington Acad.  Sci.  Jour.,  vol.  5,  p.  198,  1915. 

DULLER,  M.  L. :  Carbon  Ratios  in  Carboniferous  Coals  of  Oklahoma  and 
Their  Relation  to  Petroleum.  Econ.  Geology,  vol.  15,  p.  232,  1920. 


METAMORPHISM  OF  PETROLEUM 


175 


nt 
Fui 


is 

-o^ 


• 


176 


GEOLOGY  OF  PETROLEUM 


FIG.  76. — Isovol  map  of  Oklahoma.  (After  Fuller.} 


METAMORPHISM  OF  PETROLEUM 


111 


In  north-central  Texas  many  of  the  oil  pools  are  associated  with 
strata  that  contain  coals.  The  coals  become  richer  in  fixed  carbon 
toward  the  east.  Nearly  all  the  oil  pools  lie  between  the  50  and 
the  55  per  cent  isovol  (See  Fig.  77).  In  the  belts  yielding  coals 


FIG.  77. — Sketch  map  showing  isovols  and  relation  of  oil  pools  to  carbon  ratios 
of  coals  in  Northern  Texas.   (After  Fuller.) 

that  carry  between  55  and  60  per  cent  of  fixed  carbon  some  oil  is 
present,  with  considerable  gas.  East  of  the  line  showing  60  per 
cent  fixed  carbon  no  commercial  accumulations  have  been 
developed. 


178 


GEOLOGY  OF  PETROLEUM 


It  is  noteworthy  that  in  southern  California,  Rumania,  and 
Galicia  oil  pools  are  found  in  rocks  that  have  been  closely  folded 
and  intensely  faulted.  In  such  surroundings  large  quantities  of 
petroleum,  much  of  it  of  heavy  grade,  remain.  In  these  regions 
the  strata  include  unconsolidated  clays  or  marls  that  have  prob- 

RELATION  OF  OIL  AND  GAS  TO  CARBON  IN  CoALa 


Carbon 
Ratios 

(Surface) 

Prevailing 
Characteristics 
of  Sands 

Prevailing  Water 
Conditions  (in  Mixed 
Formations)  6 

Production6 

Over  70 

Hard  and  tight. 

Tight,    with    a    few 
porous  spots. 

Variable,    with   por- 
ous beds  of  limited 
extent. 

Fairly  continuous 
and  open. 

Softer,     less     firmly 
consolidated,    and 
more  continuous 
and  porous. 
Usually  unconsoli- 
dated. 

Water   usually   absent 
except  near  surface. 
Water  usually  absent 
below  1,500  feet. 

Water   usually   absent 
below     2,500    feet 
(often    below    2,000 
feet). 

Water   usually   absent 
below  3,000  feet 
(often    below    2,500 
feet). 
Water  usually   absent 
below  3,000-3,500 
feet. 

Sands  usually  satu- 
rated to  all  depths 
reached  by  wells. 

No  oil  or  gas,  with  rare  excep- 
tions. 
Usually  only  "shows'  '  or  small 
pockets.     No     commercial 
production. 
Commercial  pools   rare,   but 
oil    of    exceptionally    high 
grade    when    found.     Gas 
wells  common,  but  usually 
isolated  rather  than  in  pools. 
Principal  fields  of  light  oils 
and  gas  of  the  world. 

Principal  fields  of  medium  oils 
of  Ohio-Indiana  and  Mid- 
Continent  fields. 

Fields  of  heavy  Coastal  Plain 
oils  and  of  unconsolidated 
Tertiary    or    other    forma- 
tions. 

65-70 

60-65  
55-60      .     . 

50-55 

Under  50  

"FULLER,  M.  L. :  Relation  of  Oil  to  Carbon  Ratios  of  Pennsylvanian  Coals  in  North  Texas. 
Econ.  Geology,  vol.  14,  p.  538,  1919. 

6Unusually  porous  sands  like  the  Dakota  of  the  West  and  the  St.  Peter  of  the  East  carry 
water  in  quantities  far  above  the  average  and  to  far  greater  depths  and  distances  from  the 
outcrops.  Water  is  also  carried  in  fissures. 

Statements  of  quality  anply  to  oils  from  sandstones ;  oils  from  limestones  are  usually  heavier. 


ably  sealed  the  faults  as  they  were  being  formed.  Deformation 
of  the  petroliferous  strata  probably  took  place  under  much  thinner 
cover  than  in  the  Appalachian  and  Mid-Continent  fields.  As  has 
been  pointed  out  by  Fuller,  the  fixed  carbon  in  coals  doubtless 
increases  with  depth,  and  in  certain  regions,  as  would  be  expected, 


METAMORPHISM  OF  PETROLEUM  .  179 

the  oils  are  lighter  and  higher  grade  in  the  deeper  sands.  Intense 
deformation  probably  does  not  result  in  metamorphism  of  oil  to 
form  the  higher  grades  and  gas,  unless  there  is  a  considerable  cover 
above  the  petroliferous  strata. l 

Attempts  have  been  made  to  ascertain  whether  the  fixed-carbon  content 
of  carbonaceous  shales  shows  a  similar  correspondence  to  the  character  of 
petroleum  associated  with  the  shales.  According  to  Fuller,  the  results  are 
inconclusive  (1919). 


CHAPTER  XIII 
GAS  PRESSURE  AND  OIL  RECOVERY 

Gas  Pressure. — Whenever  petroleum  is  formed  gas  is  probably 
generated.  Oil  absorbs  gas,  the  amount  absorbed  depending  upon 
the  pressure.  Whether  the  oil  and  gas  are  formed  before  or  after 
deformation  of  the  strata,  the  gas  tends  to  accumulate  in  the 
highest  parts  of  a  closed  fold.  If,  however,  there  is  enough  oil  to 
absorb  the  gas  present  at  the  prevailing  pressure,  it  will  be  com- 
pletely absorbed,  and  oil  and  gas  will  issue  together  from  a  boring 
sunk  to  the  top  of  a  high  fold.  At  the  temperature  and  pressure 
that  prevail  in  most  fields,  methane  and  ethane  are  probably 
always  in  the  gaseous  state,  though  some  of  the  heavier  gases  that 
issue  in  the  gaseous  state  may  be  liquids  in  the  reservoirs.  Pen- 


FIG.  78. — Sketch  illustrating  a  gas  pool  with  underlying  water  body  in  sand 
connected  freely  .with  surface.  The  level  of  ground  water  is  assumed  to  be  at 
the  surface.  Theoretically  the  pressure  should  equal  the  weight  of  a  column 
of  water  as  high  as  ab. 

tane  and  hexane  are  liquid.     They  are  the  chief  constituents  of 
gasoline. 

If  the  gas  accumulates  at  the  top  of  the  fold  it  exerts  a  pressure 
on  the  oil  and  tends  to  drive  it  to  a  lower  structural  position.  The 
oil  in  turn  drives  down  the  water.  If  the  reservoir  rock  communi- 
cates with  the  surface  of  the  earth  at  any  place  and  is  permeable 
the  water  will  flow  out  of  the  reservoir.  Thus  the  gas  pressure 
will  equal  the  weight  of  a  column  of  water  as  high  as  the  difference 
between  the  elevation  of  the  gas  body  and  the  surface  opening 
where  the  reservoir  rock  crops  out.  (See  Fig.  78.) 

In  New  York,  according  to  Orton,1  the  gas  pressure  at  many 
^RTON,  EDWARD:  Petroleum  and  Natural  Gas  in  New  York.     New  York 
State  Mus.  Bull,  vol.  6,  No,  30,  p.  488,  1899, 

180 


GAS  PRESSURE  AND  OIL  RECOVERY  181 

places  is  independent  of  depth.     In  Pennsylvania,  according  to 
I.  C.  White,1  the  gas  pressure  generally  increases  with  depth. 

In  Oklahoma,  according  to  Gardner,2  the  gas  pressure  in  many 
wells  is  about  that  of  a  column  of  water  equal  in  length  to  the 
depth  of  the  well — or>  in  other  words,  43.4  pounds  to  the  square 
inch  for  each  100  feet  of  depth.  The  well  pressure  is  usually  some- 
what more  or  less  than  this  figure,  owing  partly  to  differences  in 
weight  of  water  due  to  differences  of  salinity.  The  gas  pressure 
moreover,  is  evidently  not  everywhere  a  reactive  pressure  against 
a  water  head.  A  well  at  Gushing  2,600  feet  deep  gave  a  gas  pres- 
sure of  1,120  pounds;  figuring  the  theoretical  hydrostatic  pressure 
of  43.4  pounds  per  hundred  feet  gives  1,128.4  pounds.  A  well  near 
Claremore,  at  a  depth  of  860  feet,  gave  a  pressure  of  375  pounds; 
the  theoretical  pressure  as  above  calculated  is  373.2.  A  well  near 
Collinsville,  at  a  depth  of  1,100  feet,  gave  a  pressure  of  495  pounds; 
the  theoretical  head  at  this  depth  is  477.4  pounds.  These  were 
closed  pressures  on  new  wells.  On  the  other  hand,  some  pressures 
are  below  what  would  be  expected.  Haworth  reported  a  well  in 
Kansas  1,000  feet  deep  with  a  pressure  250  pounds  to  the  square 
inch,  whereas  one-half  a  mile  away  900  feet  deep  showed  375 
pounds. 

Lenses  of  sand  that  are  completely  sealed  may  contain  gas 
deposits  under  pressures  that  are  independent  of  their  depth.  As 
deposits  on  monoclines  are  generally  sealed  above,  and  as  many 
of  them  are  also  sealed  below,  gas  deposits  on  monoclines  are  likely 
to  exhibit  pressures  independent  of  depths.  As  pointed  out  else- 
where, petroleum  is  probably  converted  to  gas  by  heat  and  pres- 
sure attending  dynamic  metamorphism.  As  stated  by  White  and 
by  Fuller,  the  amount  of  metamorphism  sufficient  to  change  coals 
so  that  their  carbon  ratio  equals  65  per  cent  or  more  is  probably 
sufficient  to  convert  oil  to  gas.  In  general,  heat  and  pressure 
increase  with  depth,  so  that  the  amounts  of  gas,  and  therefore  the 
gas  pressure,  will  increase.  Thus  an  increase  of  gas  pressure  with 
depth  may  be  expected,  whether  the  gas  pressure  is  balanced  by 
hydrostatic  pressure  or  not. 


,  I.  C. :  The  Mannington  Oil  Field.     Geol.  Soc.  America  Bull,  vol.  3, 
p.  196,  1892. 

"GARDNER,  J.  H. :  The  Mid-Continent  Oil  Fields.      Geol.  Soc.  America  Bull, 
vol.  28,  p.  702,  1916. 


182 


GEOLOGY  OF  PETROLEUM 


INITIAL  GAS  PRESSURES  AT  DIFFERENT  DEPTHS  IN  SEVERAL  GAS  FIELDS 
(Prepared  by  Mills  and  Wells) 


Name  of  Bed 

Locality 

Depth 
(Feet) 

Initial 
Gas 
Pressure 
(Pounds 
per 
Square 
Inch) 

Average 
Pressure 
per 
100  Feet 
Depth 
(Pounds 
per  Square 
Inch) 

Authority 

Salt  sand  
Big  lime  sand  

Keener  sand 

Woodsfield,  Ohio 
Southwest  corner  of 
Wayne  Township,  Bel- 
mont  County,  Ohio 
Southeast  corner  of  Ma- 
laga Township,  Monroe 
County,  Ohio 
Wayne  Township,  Bel- 
mont  County,  Ohio 
Woodsfield,  Ohio 

1,295 
1,310 

1,412 

1,465 
1,515 

280 
365 

400 

440 
475 

22 

28 

28 

30 
31 

Mills  and  Wells 
Do. 

Do. 

Do. 
Do. 

Big  Injun  sand  
Berea  sand  

Butler  gas  sana  

Hundred-foot  sand  .  .  . 
Third  sand  

Woodsfield,  Ohio 
Woodsfield,  Ohio 
Summerfield,  Ohio 
Sunsbury  Township, 
Monroe  County,  Ohio 
Summit  Township,  But- 
ler   County,    Pennsyl- 
vania 
Butler,  Pennsylvania 
Butler,  Pennsylvania 

1,468 
2,090 
1,698 
2,060 

1,200 

,400 
,700 

500 
710 
565 
735 

380 

780 

785 

34 
34 
33 
36 

32 

56 
46 

Do. 
Do. 
Do. 
Do. 

Do. 

Do. 
Do. 

Fourth  sand  

Butler,  Pennsylvania 
Butler,  Pennsylvania 

,452 
,800 

600 
870 

41 

48 

Do. 
Do. 

Fifth  sand  
"Clinton"  sand 

Butler,  Pennsylvania 
Butler,  Pennsylvania 
Harrison  Township, 

,568 
,950 
2  ,700 

225 
870 
810 

14 
45 
30 

Do. 
Do. 
Do. 

Trenton  limestone.  .  .  . 

Knox  County,  Ohio 
Cleveland,  Ohio 
Newberg,  Ohio 
Findlay,  Ohio 
Kokomo,  Indiana 
Cleveland,  Ohio 
Barbour    County,    West 

/2  ,500 
\2  ,900 
3,000 
950 
650 
4,500 
4  ,090 

800 
1,100 
425 
400-450 
328 
37 
1  ,800 

}  32-38 
14 
42-47 
50 
0.82 
44 

Rogers0 
Van  Horn& 
Ortonc 
Do. 
Van  Horn& 
I.  C.  White** 

(?) 

Virginia 
West  Virginia 

2,989 

1  ,420 

47 

Do. 

a)::::::::::::::::: 
(?) 

Havre,  Montana 
Havre,  Montana 

947 
1  ,370 

490 
540 

52 

39 

Stebinger8 
Do. 

<?)::::::::::::::.:: 

Unconsolidated  sand.  . 
(?)  -  

Louisiana 
Louisiana 
Loco,  Oklahoma 

1,650 
1  ,800 
750 

650 
600 
310 

39 
33 
41 

Knapp/ 
Do.ff 
McMurray  and 
Lewis^ 

aRoGER8,  G.  S.:  The  Cleveland  Gas  Field,  Cuyahoga  County,  Ohio.  U.  S.  Geol.  Survey 
Bull.  661,  p.  37,  1917 

6VAN  HORN,  F.  R.:  Reservoir  Gas  and  Oil  in  the  Vicinity  of  Cleveland,  Ohio.  Am.  Inst. 
Min.  Eng.  Trans.,  vol.  56,  p.  839,  1917. 

CORTON,  EDWARD:  The  Trenton  Limestone  As  a  Source  of  Petroleum  and  Natural  Gas  in 
Ohio  and  Indiana.  U.  S.  Geol.  Survey  Eighth  Ann.  Rept.,  p.  645,  1889. 

^Personal  communication. 

eSTEBiNGER,  EUGENE:  Possibilities  of  Oil  and  Gas  in  North-Central  Montana.  U.  S.  Geol. 
Survey  Bull.  641,  p.  73,  1916. 

•^ KNAPP,  I.  N.:  Discussion  of  Paper  by  R.  W.  JOHNSON,  The  Role  and  Fate  of  Connate  Water 
in  Oil  and  Gas  Sands.  Am.  Inst.  Min.  Eng.  Trans.,  vol.  51,  p.  593,  1915. 

^KNAPP,  I.  N.:  Discussion  of  Paper  by  W.  H.  KOBBE,  The  Recovery  of  Petroleum  from 
Unconsolidated  Sands.  Idem,  vol.  56,  p.  825,  1917. 

''McMuRRAY,  W.  F.,  and  LEWIS,  J.  O.:  Underground  Wastes  in  Oil  and  Gas  Fields  and 
Methods  of  Prevention.  Bur.  Mines  Tech.  Paper  130,  p.  13,  1916. 


GAS  PRESSURE  AND  OIL  RECOVERY  183 

The  table,  prepared  by  Mills  and  Wells,1  (p.  182)  shows  the  gas 
pressures  in  many  reservoirs  and  the  depth  of  the  wells.  The 
fifth  column  shows  the  pressures  per  100  feet  of  depth.  The 
differences  are  noteworthy.  In  most  of  these  districts,  at  least, 
it  is  highly  improbable  that  the  gas  bodies  are  in  equilibrium  with 
a  water  column  connecting  with  the  surface.  Evidently  the 
reservoirs  did  not  communicate  freely  with  the  surface. 

Behavior  of  Certain  Wells  That  Yield  Oil  and  Gas.—  Some  bor- 
ings that  penetrate  reservoirs  yield  initially  large  amounts  of  oil 
that  flows  from  the  well  and  may  be  thrown  under  pressure  high 
above  the  derrick  floor.  Such  wells  are  termed  "gushers"  in  the 
United  States  and  "spouters"  or  "fountains"  in  foreign  fields  that 
are  developed  by  the  British.  They  are  characteristic  of  fields 
that  have  reservoirs  containing  gas  under  high  pressure.  Produc- 
tion may  increase  for  a  few  days  while  drainage  lines  are  being 
established  in  the  reservoir,  but  almost  invariably  the  initial  pro- 
duction declines  rapidly  after  a  short  period.  The  gas,  under 
pressure,  forces  out  the  oil  into  the  boring  and  causes  it  to  rise 
vertically.  Sand  and  gravel  frequently  rise  with  the  oil  and  gas. 
A  well  that  penetrates  only  the  top  of  a  sand  reservoir  may  "drill 
itself  in,"  or  sink  to  the  bottom  of  the  reservoir  while  sand  is  being 
expelled  with  the  oil.  This  process  is  commonly  attended  by  in- 
creased production  during  the  early  stages  of  the  well's  life. 

Since  the  pressure  of  gas  forces  oil  out  of  the  rocks  into  the  wells, 
its  pressure  is  of  great  economic  interest.  In  porous  rocks  the 
decline  of  gas  pressure  over  a  field  is  approximately  uniform. 
Every  thousand  feet  of  gas  that  is  lost  in  general  tends  to  lower  the 
pressure.  The  practice  of  allowing  the  gas  to  issue  freely  in  open 
wells  is  now  forbidden  by  law  in  many  states.  Good  pressure  in  a 
field  after  a  long  period  of  production  is  looked  upon  as  a  favorable 
indication  for  its  future. 

Some  wells  that  at  first  yield  gas  subsequently  yield  oil.  Indeed, 
it  is  a  common,  though  wasteful  practice  to  allow  gas  to  escape 
from  a  well  in  the  hope  that  ultimately  the  well  will  produce  oil. 
Not  only  is  the  gas  wasted,  but  oil  also  is  likely  to  be  wasted, 
because  the  gas  is  the  means  by  which  the  oil  is  expelled  from  the 
rocks.  If  a  small  pocket  of  gas  has  accumulated  at  some  high 


R.  V.  A.,  and  WELLS,  R.  C.  :  The  Evaporation  and  Concentration 
of  Waters  Associated  with  Petroleum  and  Natural  Gas.  U.  S.  Geol.  Survey 
Bull.  693,  p.  28,  1919. 


184 


GEOLOGY  OF  PETROLEUM 


point  in  the  roof  of  a  reservoir  and  is  punctured  by  a  drill  gas  will 
rise  first  and  later  oil,  which  is  under  pressure.  This  is  illustrated 
in  Well  1,  Fig.  79.  If  a  gas  well  is  on  the  flank  of  a  fold  near  the 
contact  of  gas  and  oil,  it  is  obvious  that  release  of  the  gas  pressure 
which  holds  the  oil  down  will  permit  the  oil  to  rise  higher  in  the 
reservoir,  or  to  be  pushed  up  by  water  pressure.  Thus  in  Well 
2,  Fig.  79,  gas  would  issue  first,  and  oil  later.  Some  wells 
yield  petroleum  first  and  salt  water  later.  Well  3,  Fig  79,  would 
be  first  a  petroleum  well,  and  as  the  pressure  declined  and  petro- 
leum was  removed  from  the  reservoir,  salt  water  would  rise  to  take 
its  place.  Many  petroleum  wells  become  salt-water  wells.  A 
famous  example  is  the  Dos  Bocas  well,  in  Mexico,  which  after 
yielding  oil  at  the  rate  of  100,000  barrels  a  day  for  58  days,  began 
to  spout  water  in  large  quantities. 

Many  oil  wells  flow  by  heads,  or  spout  periodically  like  geysers. 
The  bore  is  gradually  filled  with  oil,  and  gas  accumulates  below, 


FIG.  79. — Sketch  showing  gas  wells  (1  and  2,)  that  would  become  oil  wells 
if,  because  of  decrease  of  pressure  of  gas,  the  plane  of  contact  of  oil  and  gas 
were  to  rise.  If  the  plane  of  contact  between  oil  and  water  were  elevated 
because  of  removal  of  gas  or  oil,  well  3  would  cease  to  flow  oil  and  would  flow 
water. 

until  the  pressure  is  sufficient  to  cause  the  oil  to  overflow.  As  the 
oil  flows  out  the  casing  head,  pressure  is  relieved  and  that  allows 
the  gas  to  expand  suddenly  and  to  raise  the  column  of  oil  with  force. 

Some  flowing  wells,  after  being  capped  and  reopened  will  cease 
to  flow.  In  other  cases  if  the  flow  of  the  oil  is  stopped  it  may  not 
be  re-established  in  its  original  force.  As  a  result  many  operators 
prefer  not  to  shut  off  a  well  entirely,  but  to  allow  it  to  flow  at  a  low 
rate  during  the  period  that  preparations  are  made  to  dispose  of 
the  oil.  In  some  cases  the  gas  pressure  has  been  reduced  by  other 
wells  tapping  the  reservoir  between  the  time  of  closing  and  reopen- 
ing the  well. 

When  a  reservoir  containing  gas  is  pierced  by  a  boring  and  the 
pressure  is  decreased  by  the  issue  of  gas,  a  series  of  changes  in 


GAS  PRESSURE  AND  OIL  RECOVERY 


185 


TOO         T 


§  500 


j>  400 


300- 


100 


70 


September,  1917 


FIG.  80. — Chart  showing  relation  of  rock  pressure  to  production  of  oil  in  a  well 
in  Midway  field,  California.   (After  Beat.) 


FIG.   81. — Composite  decline   curve  for  the   Bartlesville  field,   Oklahoma. 

(After  Beal.) 


186 


GEOLOGY  OF  PETROLEUM 


equilibrium  results.  Expansion  lowers  the  temperature  of  the  gas, 
and  the  salt-water  spray  which  is  commonly  present  in  the  issuing 
gas  will  be  cooled.  Gas  under  low  pressure  will  absorb  more  water 
than  gas  under  high  pressure,  and  evaporation  results.  As  a  result 
of  the  cooling  and  evaporation,  much  salt  is  deposited.  The  cas- 
ings of  wells  and  the  interstices  of  sands  may  be  filled  with  sodium 
chloride  so  that  the  well  will  cease  to  flow.1  Calcium  carbonate, 
magnesium  carbonate,  iron  carbonate,  and  calcium,  barium, 
and  strontium  sulphates  are  deposited  in  casings  and  presumably 
also  in  interstices  of  sands  in  reservoirs. 

Paraffin  wax  is  commonly  dissolved  in  oil.     Cooling   follows 


40*0, 


350 


50 


Year 

FIG.  82. — Generalized  decline  curve  of  the  wells  in  the  eastern  part  of  the 
Osage  Indian  Reservation,  Oklahoma.   (After  Seal.) 

relief  of  pressure.     In  some  wells  the  wax  is  deposited  in  quantities 
so  great  as  to  retard  production. 

The  life  of  most  oil  wells  is  comparatively  short.  Some  start 
flowing  at  high  rates,  many  spouting  5,000  or  10,000  barrels  a  day 
or  more.  As  a  rule  they  decline  rapidly  and  steadily  after  they 
have  reached  their  maximum,  which  is  generally  during  the  first 
few  days.  The  first  year's  flow  is  usually  much  greater  than  the 
yield  of  any  other  year.  Curves  showing  the  rates  of  decline  for 
several  fields  are  given  in  Figs.  80  to  84.  The  numbers  at  yearly 

^ILLS,  R.  V.  A.,  and  WELLS,  R.  C. :  The  Evaporation  and  Concentra- 
tion of  Water  Associated  with  Petroleum  and  Natural  Gas.  U.  S.  Geol. 
Survey  Bull.  693,  pp.  44-50,  1919. 


GAS  PRESSURE  AND  OIL  RECOVERY 


187 


1  in  fir$tyGar(  barrel 
P  4*  oi  <s> 

D  0  0  0 

4 

• 

( 

r 

« 

| 

• 

Daily  production  per  we 
o  5  8  ,  \ 

L,        i 

•   ( 

J\VG 

r&g^ 

•    ' 

• 

• 

^. 

^if' 

^  *** 

• 
• 

„  —-  ' 

i 

1 

)       10       20       30      40       50      60      70      80      90      100      UO      ^0      130      140    I5( 

I  nit  id  I  production  (first  Z4  hours) 

FIG.  83. — Curve  showing  relation  of  initial  production  to  average  daily 
production  per  well  during  the  first  year  in  the  Lawrence  County  field.  Illinois. 
(After  Deal.) 

intervals  on  the  curves  of  Figs.  81  and  84  represent  the  number 
of  properties  employed  in  determining  averages  of  each  year. 

In  estimating  the  future  production  of  a  field,  two  methods  are 
employed.  In  one,  curves  such  as  those  prepared  by  Beal  are  used. 


1906        ,1907          1908          1909          1910  19  H  I9l?          1911 


FIG.  84. — Curves  showing  the  decrease  in  daily  production  during  the  first 
year  on  several  properties  in  the  Bird  Creek-Flatrock  field,  Oklahoma,  and  in 
the  Lawrence  County,  Illinois,  pool.  The  numbers  on  the  curves  show  the 
number  of  wells  used  to  obtain  the  data.  (After  Beal.} 


188 


GEOLOGY  OF  PETROLEUM 


In  the  other  the  volume,  porosity,  and  saturation  of  the  sands  and 
the  amount  of  oil  which  may  eventually  be  recovered  are  estimated 
from  the  data  available.  The  latter  method,  which  has  been 
developed  by  Washburne  and  others,  is  a  useful  check  on  the 
curves  showing  decline  of  wells,  but  the  results  are  not  expected  to 
be  precisely  accurate  because  the  determinations  are  affected  by 
many  variable  factors,  and  generally  not  all  of  these  are  known. 

VOLUME  OP  A  HORIZONTAL  SAND,  PER  HECTARE  AND  PER  ACRE* 


Area 

Thickness  of 
Sand 

Volume  of  Sandb 

Cubie  Meters 

Barrels  of  42 
United  States 
Gallons 

1  hectare  

1  meter 
Ifoot 
1  foot 

10,000 
3,048 
1,233 

62  ,898 

19  ,171 

7,758 

1  hectare 

1  acre  

°WASHBTTBNB,  C.  W.:  The  Estimation  of  Oil  Reserves.  Am.  lust.  Min.  Eng.  Trans.,  vol.  51, 
p.  646,  1916. 

bThe  figures  of  the  last  column  multiplied  by  the  thickness  of  the  sand,  by  the  porosity,  and 
by  the  relative  saturation  give  the  capacity  of  the  sand  in  barrels  per  unit  area.  Thus,  a  sand 
12  feet  thick,  with  a  porosity  of  15  per  cent  and  a  relative  saturation  of  75  per  cent,  contains 
12X0.15X0.75X7,758=10,473  barrels  per  acre.  With  an  assumed  extraction  factor  of  60 
per  cent,  each  acre  would  produce  6,284  barrels. 


The  data  showing  decrease  of  yield  of  groups  of  wells  in  a  district 
may  be  presented  in  many  ways,  as  shown  in  a  recently  issued 
bulletin  by  Beal. l  Each  method  exhibits  certain  advantages  under 
certain  sets  of  conditions.  , 

It  is  noteworthy  that  not  only  does  the  yield  of  individual  wells 
diminish  rapidly, but  the  initial  yields  and  total  production  of  wells 
generally  diminish  steadily  as  more  wells  are  put  down  in  the  field. 

Probably  half  the  oil  in  some  reservoirs  remains  in  the  rocks  after 
the  fields  have  ceased  to  yield.  It  adheres  to  sand  grains,  and  in 

!BEAL,  C.  H. :  The  Decline  and  Ultimate  Production  of  Oil  Wells,  with  Notes 
on  the  Valuation  of  Oil  Properties.  U.  S.  Bur.  Mines  Bull  177,  pp.  1-215, 
1919. 


GAS  PRESSURE  AND  OIL  RECOVERY  189 

the  absence  of  gas  under  pressure  it  can  not  be  moved  (Fig.  85). 
By  proper  management  and  conservation  of  gas  pressure,  the 
maximum  yields  may  be  obtained.  If  the  gas  is  tapped  above 
the  oil  and  the  gas  pressure  is  wasted  without  allowing  the  gas  to 
do  its  work,  it  may  be  impossible  to  obtain  the  principal  part  of 
the  oil  stored  in  the  rocks.  It  is  common  practice  to  increase  the 
flow  by  pumping  the  sands  to  a  vacuum.  Another  method  con- 
sists in  driving  water  into  the  sands  and  floating  the  oil  to  points 
of  issue.  Thus  water  that  is  allowed  to  enter  the  sands  in  one 
well  will  make  its  way  down  the  dip  to  another  well,  pushing  the 


FIG.  85. — Sketch  illustrating  a  pile  of  sand  grains,  and  showing  how  oil  is 
retained  by  adhesion.  (After  Lewis.) 

oil  ahead  of  it.  A  third  method  consists  in  pumping  compressed 
air  into  the  sands.  Natural  gas  is  used  in  some  fields  instead  of 
air  and  has  the  advantage  that  it  absorbs  the  gasoline,  which  may 
be  recovered  by  condensing  the  gas  after  it  has  issued  from  the 
wells.  These  methods1  prolong  the  life  and  increase  the  produc- 
tion of  a  field,  but  they  are  generally  not  employed  until  the  field 
is  near  exhaustion. 

1LEWis,  J.  O. :  Methods  for  Increasing  the  Recovery  from  Oil  Sands.     U.  S. 
Bur.  Mines  Bull.  148,  pp.  1-128,  1917. 


CHAPTER  XIV 

PETROLIFEROUS  PROVINCES  AND  PETROLEOGENIC 

EPOCHS 

Petrologists  have  long  used  the  term  "petrographic  province" 
for  a  district  or  region  that  contains  bodies  of  igneous  rocks  which, 
though  differing  somewhat  in  composition  and  character,  never- 
theless exhibit  similar  features  that  indicate  similar  generic 
relations.  Similarly,  the  ore  deposits  of  certain  regions  that  have 
common  characteristics  are  grouped  within  a  metallogenic 
province. 1 

The  term  "petroliferous  province,"  first  used  by  Woodruff,2 
suggests  a  region  containing  accumulations  of  petroleum  that  are 
nearly  related  genetically  and  that  have  closely  similar  geologic 
surroundings. 

Schuchert3  classifies  areas  as  regards  petroliferous  possibilities 
as  follows: 

1.  The  impossible  areas  for  petroliferous  rocks. 

(a)  The  more  extensive  areas  of  igneous  rocks  and  especially 
those  of  the  ancient  shields :  exception,  the  smaller  dikes. 
(6)  All  pre-Cambrian  strata. 

(c)  All  decidedly  folded  mountainous  tracts  older  than  the 
Cretaceous;     exceptions,      domed     and     block-faulted 
mountains. 

(d)  All  regionally  metamorphosed  strata. 

(e)  Practically  all  continental  or  fresh-water  deposits;  relic 
seas,  so  long  as  they  are  partly  salty,  and  saline  lakes  are 
excluded  from  this  classification. 

^INDGREN,  WALDEMAR:  The  Geological  Features  of  the  Gold  Production 
of  North  America.  Am.  Inst.  Min.  Eng.  Trans.,  vol.  33,  pp.  790-845,  1903; 
Metallogenetic  Epochs.  Econ.  Geology,  vol.  4,  pp.  409-420,  1909. 

EMMONS,  W.  H. :  The  Principles  of  Economic  Geology,  pp.  269-270,  1918. 

2WooDRUFF,  E.  G.:  Petroliferous  Provinces.  Am.  Inst.  Min.  Eng.  Bull. 
150,  pp.  907-612,  1919. 

SCHUCHERT,  CHARLES:  Petroliferous  Provinces;  Discussion  of  Paper  of 
E.  G.  WOODRUFF.  Am.  Inst.  Min.  Eng.  Bull.  155,  p.  3059-3060,  1919. 

190 


PETROLIFEROUS  PROVINCES  191 

(/)  Practically  all  marine  formations  that  are  thick  and  uni- 
form in  rock  character  and  that  are  devoid  of  interbedded 
dark  shales,  thin-bedded  dark  impure  limestones,  dark 
marls,  or  thin-bedded  limy  and  fossiliferous  sandstones. 

(g)  Practically  all  oceanic  abyssal  deposits;  these,  however, 
are  but  rarely  present  on  the  continents. 

2.  Possible  petroliferous  areas. 

(a)  Highly  folded  marine  and  brackish  water  strata  younger 
than  the  Jurassic,  but  more  especially  those  of  Cenozoic 
time. 

(6)  Cambrian  and  Ordovician  gently  folded  strata. 

(c)  Lake  deposits  formed  under  arid  climates  that  cause  the 
waters  to  become  saline;  it  appears  that  only  in  salty 
waters  (not  over  4  per  cent?)  are  the  bituminous  mate- 
rials made  and  preserved  in  the  form  of  kerogen,  the 
source  of  petroleum;  some  of  the  Green  River  (Eocene) 
continental  deposits  (the  oil  shales  of  Utah  and  Colorado) 
may  be  of  saline  lakes. 

3.  Petroliferous  areas. 

(a)  All  marine  and  brackish  water  strata  younger  than  the 
Ordovician  and  but  slightly  warped,  faulted,  or  folded; 
here  are  included  also  the  marine  and  brackish  deposits 
of  relic  seas  like  the  Caspian,  formed  during  the  later 
Cenozoic.     The  more  certain  oil-bearing  strata  are  the 
porous  thin-bedded  sandstones,  limestones,  and  dolomites 
that  are  interbedded  with  black,  brown,  blue,  or  green 
shales.     Coal-bearing   strata   of  fresh-water   origin   are 
excluded.     Series  of  strata  with  disconformities  may  also 
be  petroliferous,  because  beneath  former  erosional  sur- 
faces the  top  strata  have  induced  porosity  and  therefore 
are  possible  reservoir  rocks. 

(b)  All  marine  strata  that  are,  roughly,  within  100  miles  of 
former  lands;  here  are  more  apt  to  occur  the  alternating 
series  of  thin-  and  thick-bedded  sandstones  and  limestones 
interbedded  with  shale  zones. 

Perhaps  the  greatest  petroliferous  province  is  the  Tertiary  prov  • 
ince  of  Eurasia,  which  includes  all  the  important  producing  oil 
fields  of  the  Old  World,  except  England  and  Germany.  In  the 


192  GEOLOGY  OF  PETROLEUM 

producing  fields  of  Alsace,  Galicia,  Rumania,  the  Caucasus, 
Turkey,  Persia,  Burma,  Oceanica,  and  Japan,  nearly  all  the  petro- 
leum is  derived  from  Tertiary  rocks,  except  some  of  that  produced 
in  Galician  fields,  which  comes  from  the  Upper  Cretaceous. 
The  greater  part  of  the  oil  from  the  Tertiary  beds  is  obtained  from 
the  Miocene  and  Oligocene.  The  oil  is  accumulated  in  raised 
structures  except  where  there  has  been  extensive  folding  and  fault- 
ing of  unconsolidated  rocks  near  the  surface.  In  general  the  rocks 
of  this  province  are  not  thoroughly  consolidated.  Although  some 
of  the  oil  is  a  high-grade  light  oil,  with  paraffin  base,  a  larger  part 
of  it  is  low-grade  asphaltic  oil.  The  characteristic  structural 
features  are  domes  and  anticlines,  although  oil  is  found  in  faulted 
monoclines  in  Alsace,  in  synclines  at  Boryslaw,  at  an  unconformity 
in  Maikop,  and  in  fault  traps  and  near  salt  plugs  in  Rumania. 
Deformation  affecting  the  petroliferous  strata  took  place  in  all 
these  areas  in  the  later  part  of  Tertiary  time.  There  is  not  a  con- 
tinuous belt  of  Tertiary  strata  between  the  oil-bearing  regions 
named.  At  some  places  the  Tertiary  has  been  eroded;  at  other 
places  there  were  probably  islands  or  larger  land  masses  between 
the  Tertiary  seas.  In  general,  however,  this  region  between 
Alsace,  Borneo,  and  Japan,  with  an  arm  extending  from  Borneo  to 
New  Guinea  and  thence  possibly  to  New  Zealand,  was  a  site  of 
deposition  in  early  and  middle  Tertiary  time  and  of  extensive 
deformation  later  in  the  Tertiary. 

In  the  Egypt  held,1  near  the  Gulf.of  Suez,  oil  is  found  in  Tertiary 
beds  that  were  deformed  in  late  Tertiary  time.  This  field  is 
closely  affiliated  with  the  Eurasian  province.  On  the  other  hand, 
in  the  English  field,  oil  comes  from  Paleozoic  strata  that  are  thor- 
oughly consolidated.  The  English  field  should  not  be  included 
in  the  Eurasian  province.  Certain  small  fields  in  Germany  produce 
oil  from  rocks  older  than  the  Tertiary. 

In  North  America  (Fig.  86)  the  Pacific  coast  fields  and  also  the 
Gulf  coast  field  of  Texas  and  Louisiana  are  more  closely  affiliated 
with  the  fields  of  the  Eurasian  province  than  with  the  Appalachian 
and  Mid-Continent  fields.  They  derive  their  oil  chiefly  from 
Tertiary  strata  that  were  extensively  deformed  in  late  Tertiary 
time.  The  rocks  are  not  consolidated,  as  they  are  in  the  Appalach- 
ian and  most  of  the  Mid-Continent  fields.  Most  of  the  oil,  like 

JIt  is  reported  that  oil  has  recently  been  developed  in  the  Cretaceous  in 
Egypt. 


PETROLIFEROUS  PROVINCES 


193 


the  greater  part  of  that  from  the  Eurasian  field,  is  of  low  grade, 
with  asphalt  base. 

The  Appalachian  fields,  the  Lima-Indiana  field,  and  the  Mid- 


FIG.  86. — Map  of  North  America,  showing  petroliferous  provinces  according 
the  interpretations  of  E.  G.  Woodruff.     The  lined  areas  are  in  the  main 


to 
unfavorable. 


Continent  field,  except  northern  Louisiana  and  eastern  Texas,  sup- 
ply oil  from  Paleozoic  strata  that  are  well  consolidated  but  not 
extensively  deformed.  In  general  the  oil  is  of  high  grade,  with  a 


194  GEOLOGY  OF  PETROLEUM 

paraffin,  or  paraffin  and  asphalt  base.  The  Ontario  fields  of  Lamb- 
ton  and  Middlesex  Counties  supply  oil  of  similar  character  from 
Paleozoic  strata  similarly  deformed  and  constitute  a  part  of  the 
Appalachian  province. 

The  northern  Louisiana  and  eastern  Texas  fields,  including  those 
of  the  Balcones  fault  region,  Texas,  supply  oil  from  Upper  Cre- 
taceous strata,  from  which  also  nearly  all  the  oil  produced  in 
Wyoming,  Montana,  and  Colorado  is  derived.  These  fields, 
though  far  apart,  have  certain  common  features.  Each  group 
constitutes  a  province  nearly  related  to  the  other  group. 

In  the  Caribbean  province,  including  the  West  Indies,  Trinidad, 
the  Gulf  coast  of  Mexico,  and  the  northern  part  of  South  America, 
oil  is  found  in  both  Cretaceous  and  Tertiary  rocks  in  various 
stages  of  consolidation.  The  grades  of  the  oil  show  wide 
differences. 

Petroleogenic  epocns  are  those  in  which  beds  that  contain  oil 
were  laid  down.  The  most  productive  strata  are  those  of  Pale- 
ozoic, Cretaceous,  and  Tertiary  age.  Petroleogenic  epochs  are 
discussed  in  connection  with  the  geologic  age  of  petroliferous 
strata  on  pages  10  to  15. 


CHAFER  XV 

APPALACHIAN,  LIMA-INDIANA,  AND  MICHIGAN  FIELDS 

INTRODUCTION 

The  United  States  is  divided  into  physiographic  provinces  which 
embrace  the  principal  mountain  ranges,  plateaus,  and  plains  (Fig. 
87).  The  principal  oil  fields  are  in  the  Appalachian  Plateau  and 
interior  plains ;  the  Gulf  Coastal  Plain ;  the  Rocky  Mountains ;  and 
the  California  valley  and  Coast  Range.  The  Appalachian  Plateau 
lies  west  of  and  ig  parallel  to  the  Appalachian  Mountains  and  with 


FIG.   87. — Sketch  showing  physiographic  provinces  of  the  United  States. 
(After  Blackwelder.) 

the  interior  plains  it  constitutes  the  interior  lowlands  orographic 
element.1  This  element,  which  lies  between  the  Appalachian 
Mountains  and  the  Rocky  Mountains,  contains  many  of  the 
*"An  orographic  element  is  a  region  which  is  characterized  by  certain  dis- 
tinctive geologic  features,  particularly  by  a  certain  type  of  structure  and  a 
more  or  less  unified  geologic  history.  .  .  .  The  orographic  elements  tend  to 
coincide  with  the  physiographic  provinces." — BLACKWELDER,  ELLIOTT,  United 
States  of  North  America.  Handbuch  der  Regionalen  Geologic,  Band  8,  Abt.  2, 
(Heft  11),  p.  69,  1912. 

195 


196 


GEOLOGY  OF  PETROLEUM 


largest  oil -fields  in  the  United  States.  Among  them  are  the 
Appalachian  field,  the  Lima-Indiana  field  of  Ohio  and  Indiana, 
the  Illinois-Indiana  field,  and  the  Mid-Continent  field  except  the 
Sabine  uplift,  which  is  included  with  the  Gulf  coast  field  in  the 
Coastal  Plain.  The  Rocky  Mountain  element  includes  the  fields 
of  Wyoming  and  Colorado.  Some  of  these  fields  perhaps  should 

SYMBOLS  AND  COLORS  ASSIGNED  TO  ROCK  SYSTEMS  IN  THE  UNITED  STATES'' 


Era 

System 

Series 

Symbol 

Color  for 
Sedimentary 
Rocks 

Quaternary 

Recent 
,  Pleistocene 

Q 

Brownish  yellow 

\ 

Cenozoic  

1 

Pliocene 

[Tertiary 

Miocene 
Oligocene 

>     T 

Yellow  ocher 

1  Eocene 

{  Cretaceous 

[Upper 
[Lower 

K 

Olive-green 

Mesozoic  

<  Jurassic 

Upper 
Middle 

\     J 

Blue-green 

Lower 

] 

Upper 

(Triassic 

Middle 

\     Tr 

Peacock-blue 

Lower 

Permian 

] 

Carboniferous 

Pennsylvanian 

\  c  . 

Blue 

1  Mississippian 

(Upper 

Devonian 

Middle 

D 

Blue-gray 

[Lower 

Paleozoic  

•  Silurian 

S 

Blue-purple 

(Cincinnatian 

Ordovician 

Mohawkian 

o 

Red-purple 

Lower 

Saratogan 

(Cambrian 

Acadian 

E 

Brick-red 

(Georgian 

j 

Proterozoic  

J  Algonkian 

A 

Brownish  red 

\Archean 

2R 

Gray-brown 

JU.  S.  Geological  Survey. 


APPALACHIAN,  LIMA-IND.,  AND  MICH.  FIELDS  197 


198  GEOLOGY  OF  PETROLEUM 

be  included  in  the  interior  lowlands  for  they  lie  on  foothill  folds  of 
the  Rockies  much  as  the  fields  of  the  Appalachian  geosyncline  lie 
with  respect  to  the  Appalachian  Mountains.  In  accordance  with 
the  practice  of  the  statistical  branch  of  the  United  States  Geologi- 
cal Survey,  these  are  described  with  other  fields  in  the  Rocky 
Mountain  division.  The  California  valley  and  Coast  Range  em- 
brace the  fields  of  southern  California. 

Petroleum  is  found  in  the  United  States  in  rocks  that  range  in 
age  from  Ordovician  to  Recent.  Considerable  oil  is  obtained  from 
Paleozoic,  Mesozoic,  and  Tertiary  rocks.  The  general  distribu- 
tion of  the  strata  is  shown  by  Fig.  88. 

In  the  interior  lowlands  the  prevailing  rocks  are  of  Paleozoic  age. 
The  geologic  structure  is  generally  simple,  the  rocks  dipping  at  low 
angles.  The  attitude  of  the  rocks  is  influenced  by  the  mountain 
ranges  to  the  east  and  west  of  the  lowlands  and  by  the  structural 
uplifts  which  lie  between  (Fig.  89).  These  areas  of  uplift  are  not 
much  higher  than  the  surrounding  lowlands.  They  are  anticlines, 
domes,  or  regions  of  close  folding  and  some  of  them  have  a  far- 
reaching  influence  on  the  structure  of  the  rocks  in  the  lowland  area 
around  them. 

The  Appalachian  Plateau  is  a  geosyncline  that  strikes  north- 
eastward and  parallels  the  Appalachian  Mountains.  On  it  are 
superimposed  a  number  of  parallel  folds,  the  axes  of  which  lie 
approximately  parallel  to  the  long  dimension  of  the  plateau  and 
the  Appalachian  Mountains.  The  strata  rise  gently  toward  the 
Cincinnati  geanticline,  on  which  are  developed  the  Cincinnati 
arch  in  Kentucky.  Ohio,  and  Indiana  and  the  Nashville  arch  in 
Tennessee.  West  of  the  Cincinnati  arch  the  rocks  dip  west  of 
north  toward  Indiana  and  Illinois,  where  they  form  the  great 
coal  basin  in  Illinois',  Indiana,  and  western  Kentucky.  They  rise 
again  toward  Missouri  and  Arkansas  in  the  region  of  the  Ozark 
Plateau.  The  strata  dip  away  from  the  Ozark  Plateau  in  all 
directions,  rising  toward  the  west  in  and  near  the  foothill  region  of 
the  Rocky  Mountains  and  toward  the  south  in  the  Ouachita 
Mountains. 

The  Ouachita  Mountains,  which  lie  in  central  Arkansas  and 
southern  Oklahoma,  were  formed  at  about  the  same  time  as  the 
Appalachian  Mountains  and  are  regarded  by  some  as  an  extension 
of  that  range.  The  Mississippi  embayment,  which  contains  rocks 
of  much  later  age,  separates  the  two  ranges  by  about  300  miles. 


APPALACHIAN,  LIMA-IND.,  AND  MICH.  FIELDS  199 

Close  folding  is  characteristic  of  regions  near  the  central  axes  of 
the  Appalachian  and  Ouachita  Mountains.  In  the  Rocky  Moun- 
tains the  folding  is  generally  less  intense,  yet  the  beds  are  steepty 
tilted,  so  that  at  many  places  they  lie  on  edge  or  are  overturned. 
The  Cincinnati  arch  and  the  Ozark  uplift  cover  wide  areas  but  are 
marked  by  low  dips. 


The  Ouachita  orographic  element  is  not  a  continuous  range  but 
consists  of  a  series  of  uplifts  separated  by  rocks  which  are  more 
nearly  flat-lying.  The  Ouachita  element  extends  westward  from 
Hot  Springs,  Arkansas,  into  southern  Oklahoma.  It  embraces 
the  Ouachita  Mountains  in  Arkansas,  the  Arbuckle  Mountains,  in 


200  GEOLOGY  OF  PETROLEUM 

south-central  Oklahoma;  and  the  Wichita  Mountains,  in  south- 
western Oklahoma.  Between  the  Arbuckle  and  Wichita  Moun- 
•tains  the  rocks  dip  at  comparatively  low  angles. 

South  of  the  Ouachita  Mountains,  near  the  center  of  Texas,  is 
the  Llano  uplift  of  ancient  rocks.  This  uplift,  although  its  surface 
is  rather  rugged,  does  not  rise  conspicuously  above  the  surrounding 
country,  but  its  influence  on  the  attitude  of  the  strata  is  apparent 
in  the  plains  country  far  to  the  north,  where  in  the  north  Texas 
field  large  deposits  of  petroleum  have  been  discovered. 

In  the  interior  lowlands  the  outcropping  rocks  are  mainly  Pale- 
ozoic sedimentary  beds  (Fig.  88).  Pre-Cambrian  rocks  crop  out  in 
small  areas  in  the  Ozark  Plateau,  southeastern  Missouri;  in  the 
Arbuckle  and  Wichita  Mountains,  Oklahoma;  in  central  Texas; 
and  in  larger  disconnected  areas  in  southwestern  Minnesota, 
extending  into  Iowa  and  South  Dakota.  At  some  places  ancient 
igneous  rocks,  principally  granite,  have  been  encountered  below 
the  surface.  A  deep  well  at  Holla  and  also  one  in  the  Joplin  dis- 
trict, Missouri,  were  sunk  to  granite,  and  farther  west,  in  Kansas, 
a  great  belt  of  granite  has  been  revealed  below  the  surface  by 
borings  sunk  for  oil.  Granite  is  found  also  in  wells  west  of  Minne- 
sota and  Iowa,  and  east  of  the  Rocky  Mountains.  Generally  the 
granite  is  regarded  as  pre-Pennsylvanian  and  possibly  pre-Cam- 
brian.  Gardner1  states  that  there  is  little  or  no  metamorphism 
of  the  overlying  sediments.  Possibly  some  of  the  granite  is  Car- 
boniferous or  later,  however,  for  Twenhofel2  found  at  the  Silver 
City  dome,  Woodson  County,  Kansas,  in  the  matrix  of  a  limestone 
breccia,  crystals  of  hornblende,  epidote,  and  chlorite,  suggesting 
the  presence  of  an  igneous  rock  near  by. 

The  structure  of  the  Appalachian  Mountains  resembles  that  of 
the  Ouachita  element  in  many  respects, 3  and  it  has  been  suggested 
that  the  two  areas  are  connected  below  the  beds  of  Mississippi 
embayment  by  strata  having  similar  structure.  This  correlation 
is  not  certain  for  the  regions  of  intense  deformation,  because  the 
mountain  areas  differ  in  strike.  Both  regions,  however,  are  parallel 

GARDNER,  J.  H. :  Mid-Continent  Oil  Fields.  In  Geol.  Soc.  America  Bull 
vol.  28,  p.  691,  1917. 

TWENHOFEL,  W.  H. :  The  Silver  City  Quartzites.  Geol.  Soc.  America 
Bull,  vol.  28,  pp.  419-430,  1917. 

»BRANNER,  J.  C. :  The  Former  Extension  of  the  Appalachians  Across  Missis- 
sippi, Louisiana,  and  Texas.  Amer.  Jour.  Sci.  Series  4,  vol.  4,  pp.  357-371, 
1897 


APPALACHIAN,  LIMA-IND.,  AND  MICH.  FIELDS  201 

to  the  ocean  deeps  to  the  east  and  south  and  are  evidently  related 
in  a  broad  way  to  them.  There  is,  moreover,  toward  the  lowland 
interior  a  continuous  belt  of  less  intense  deformation,  that  is  prob- 
ably related  to  the  mountain  areas. 

The  correlation  of  Appalachian  folds  with  those  that  strike 
through  Kentucky  was  first  brought  out  by  Gardner,1  who  re- 
viewed the  work  of  other  investigators,  among  them  Campbell, 
Orton,  Munn,  Muller,  and  Glenn.  Later  Reger,2  of  the  West 
Virginia  Geological  Survey,  investigated  the  same  structural 
features.  He  agrees  that  the  Rough  Creek  uplift,  the  Irvine- 
Campton  anticline,  and  the  Chestnut  Ridge  anticline  are  in  the 
same  belt  of  deformation  (Fig.  90).  The  Ozark  uplift  of  Missouri 
appears  to  be  connected  by  a  belt  of  deformed  rocks  with  the 
Appalachian  Plateau,  suggesting  that  the  greater  segments  to  the 


FIG.  90. — Sketch  map  showing  axes  of  deformation  west  of  the  Appalachian 
Mountains,  and  north  of  the  Ouchita  Mountains.  (Data  from  Gardner,  Sieben- 
thal,  and  others.) 


south — the  Ouachita  Mountains  of  Oklahoma  and  Arkansas — may 
be  connected  with  the  Appalachian  Mountains,  which  lie  east  of 
the  Appalachian  Plateau.  As  Siebenthal3  shows,  the  Ozark  axis 
extends  into  northeastern  Oklahoma.  (See  Fig.  91.) 

GARDNER,  J.  H.:  A  Stratigraphic  Disturbance  Through  the  Ohio  Valley? 
Running  from  the  Appalachian  Plateau  in  Pennsylvania  to  the  Ozark  Moun- 
tains in  Missouri.  Geol.  Soc.  America  Bull,  vol.  26,  pp.  477-483, 1915. 

2REGER,  D.  B. :  The  Possibilities  of  Deep-Sand  Oil  and  Gas  in  the  Appalach- 
ian Geosyncline  of  West  Virginia.  Am.  Inst.  Min.  Eng.  Trans.,  vol.  56,  p. 
856,  1916. 

SIEBENTHAL,  C.  E. :  Origin  of  the  Lead  and  Zinc  Deposits  of  the  Joplin 
Regions.  U.  S.  Geol.  Survey  Bull.  606,  p.  34,  1915. 


202 


GEOLOGY  OF  PETROLEUM 


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APPALACHIAN,  LIMA-IND.,  AND  MICH.  FIELDS  203 


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204 


GEOLOGY  OF  PETROLEUM 


Igneous  intrusive  rocks  are  found  at  a  few  places  along  the  line 
of  deformation.  Basic  igneous  rocks,  generally  as  dikes,  are  found 
in  Ste.  Genevieve  County,  Missouri,  intruding  the  Cambrian1 
between  the  area  of  pre-Cambrian  rocks  of  the  Ozarks  and  the 
Bald  Hill  uplift  of  southern  Illinois.  An  area  containing  basic 
dikes  and  fluorspar  veins  is  found  in  southern  Illinois  and  western 
Kentucky.2  Basic  dikes  are  found  also  in  eastern  Kentucky,3 
in  southwestern  Pennsylvania,4  and  in  central  New  York.5 


FIG.  91. — Map  showing  deformation  of  part  of  Ozark  uplift.  Figures  on 
contours  represent  approximate  elevation  of  base  of  Mississippian  limestone 
above  sea  level;  parts  shaded  with  diagonal  lines  represent  areas  in  which 
Pennsylvania  shale  is  at  the  surface;  areas  with  strokes  and  dots  represent 
exposures  of  crystalline  rocks. 

1BucKLEY,  E.  R. :  Lead  and  Zinc  Deposits  of  the  Ozark  Region,  in  Types  of 
Ore  Deposits,  p.  105,  San  Francisco,  1911. 

2ULRicH,  E.  O.,  and  SMITH,  W.  S.  T.:  The  Lead,  Zinc,  and  Fluorspar  De- 
posits of  Western  Kentucky.  U.  S.  Geol.  Survey  Prof.  Paper  36,  p.  26,  1905. 

»DILLER,  J.  S. :  Peridatite  of  Elliot  County,  Kentucky.  U.  S.  Geol.  Survey 
Bull.  38,  pp.  1-29,  1887. 

4HiCB,  R.  R. :  Pennsylvania  Geol.  Survey  Biennial  RepL,  1910-12. 

*BLACKWELDER,  ELIOT:  Op.  dt.t  p.  117. 


APPALACHIAN,  LIMA-IND.,  AND  MICH.  FIELDS  205 

West  of  the  Appalachian  Mountains,  in  the  great  Appalachian 
geosyncline,  there  are  many  parallel  folds.  Most  of  these  strike 
northeast,  parallel  to  the  Appalachian  Mountains.  The  Burning 
Springs-Volcano  anticline,  in  West  Virginia,  however,  strikes 
north,  making  a  large  angle  with  other  Appalachian  folds.  This 
anticline  is  shorter  but  much  steeper  than  the  neighboring  folds. 

The  Warfield-Campton-Rough  Creek-Bald  Hill-Ozark  axis  of 
deformation  has  been  mentioned.  It  is  probably  the  most  per- 
sistent structural  feature  of  the  lowlands  element.  The  LaSalle 
anticline  of  Illinois,  the  anticline  that  extends  from  the  Black  Hills 
into  Kansas,  and  the  Glendive  anticline  of  eastern  Montana  and 
western  North  Dakota  are  noteworthy  features. 

The  great  synclines  of  the  interior  lowlands  are  the  Appalachian 
geosyncline,  the  basin  of  the  southern  peninsula  of  Michigan,  the 
Illinois-Indiana-Kentucky  coal  basin,  and  the  great  geosyncline 
lying  east  of  the  Rocky  Mountains,  extending  to  Minnesota,  Iowa, 
Kansas,  and  Oklahoma. 

Besides  the  folds  already  mentioned  there  are  a  number  of 
smaller  undulations  in  the  interior  of  the  lowland  region,  where  the 
beds  rise  in  domes,  anticlines,  and  anticlinal  noses.  Such  folds 
have  supplied  the  gathering  grounds  for  petroleum  and  gas  in  many 
of  the  oil  fields. 

Faults  are  not  numerous  in  the  interior  lowlands,  except  in  cer- 
tain local  areas.  In  western  Kentucky  and  southern  Illinois  they 
are  closely  spaced  in  the  fluorspar  region  along  Ohio  River.  Faults 
are  found  also  in  the  oil  fields  of  eastern  Kentucky.  In  the  oil 
region  of  Oklahoma  faults  of  small  throw  are  not  uncommon,  and 
in  the  eastern  part  of  Oklahoma,  in  Cherokee,  Adair,  and  Sequoyah 
Counties,  faults  with  considerable  throw  are  rather  closely  spaced. 
A  few  faults  have  been  discovered  also  in  the  Joplin  region,  Mis- 
souri; in  northeastern  Oklahoma;  and  in  the  Sabine  uplift,  Louisi- 
ana and  Texas.  On  the  whole,  however,  the  rocks  of  the  interior 
lowlands  are  very  gently  deformed.  This  lowland  region  contains, 
indeed,  one  of  the  largest  bodies  of  Paleozoic  strata  of  the  earth 
that  has  undergone  so  little  deformation. 

The  Paleozoic  strata  of  the  lowlands  are  consolidated,  but  they 
are  not  much  metamorphosed  by  pressure.  They  consist  princi- 
pally of  shales,  sandstones,  and  limestones.  Muds,  sands,  and 
marls  are  generally  lacking,  Nowhere,  except  near  the  mountain 


206 


GEOLOGY  OF  PETROLEUM 


uplifts  are  pronounced  secondary  structural  features  developed  in 
the  shales.  They  are  rarely  slates  or  schists.  The  sandstones 
may  be  locally  altered  to  quartzite,  through  infiltration  and  cemen- 
tation. The  limestones  are  generally  recrystallized  somewhat,  but 
away  from  the  mountains  they  show  very  little  evidence  of 
deformation  by  pressure. 

APPALACHIAN  OIL  FIELD 

General  Features. — The  Appalachian  field  includes  all  the  oil 
and  gas  producing  districts  in  the  United  States  east  of  central 
Ohio  and  northeast  of  central  Alabama.  These  districts  are  in 
New  York,  Pennsylvania,  West  Virginia,  southeastern  Ohio, 


100  Miles 


FIG.  92. — Sketch  showing  the  areal  geology  of  part  of  the  Appalachian  geo- 
syncline;  11,  Permian;  12,  Pennsylvanian;  13,  Mississippian;  14,  Devonian; 
15,  Silurian;  16,  Ordovician.  (After  Willis.) 

Kentucky,  Tennessee,  and  northern  Alabama.  This  field,  which 
was  the  first  great  oil  field  in  the  world  to  be  extensively  developed, 
still  produces  about  25,000,000  barrels  annually. 

Surface  indications  of  oil  are  not  numerous,  although  they  are 
^resent  at  several  places.  Noteworthy  among  them  are  Oil 


APPALACHIAN,  LIMA-IND.,  AND  MICH.  FIELDS  207 

Spring,  Allegany  County,  New  York;  Oil  Creek,  Venango  County, 
Pennsylvania;  the  gas  seep  at  Burning  Springs,  Wirt  County, 
West  Virginia;  and  the  grahamite  dike  in  Ritchie  County,  West 
Virginia.  The  oil  from  seeps  was  gathered  by  Indians  and  by 
early  settlers  and  used  for  medicinal  purposes.  In  the  early  days 
oil  was  encountered  in  small  amounts  in  many  wells  sunk  for  brine, 
but  it  was  not  generally  regarded  with  favor  because  there  was 
little  use  for  it. 
The  Appalachian  field  is  a  great  geosyncline  that  lies  west  of  the 


YORK 


A  Kl  Al 


lOOMUes 


FIG.  93. — Structure  contour  map  of  part  of  the  Appalachian  geosyncline,  show- 
ing contours  on  the  Big  Injun  sand.   (After  Reeves.) 


Appalachian  mountain  front  and  extends  from  southwestern  New 
York  to  northern  Alabama.  On  the  west  the  strata  rise  to  the 
Cincinnati  geanticline  in  Ohio,  Kentucky,  and  Tennessee.  The 
field  is  somewhat  larger  than  the  Appalachian  coal  basin,  although 
some  of  the  most  productive  parts  of  it  are  below  the  area  occupied 
by  that  basin.  A  comparatively  small  portion  of  it  yields  oil. 
Fuller1  estimates  the  oil-bearing  areas  to  be  as  follows: 


DULLER,  M.  L. :  Appalachian  Oil  Fields.    Geol.  Soc.  America  Bull.,  vol. 
28,  p.  646,  1917. 


208  GEOLOGY  OF  PETROLEUM 

AREA  OF  APPALACHIAN  OIL  AND  GAS  POOLS,  IN  SQUARE  MILES 


Oil 

Gas 

New  York                                  

300 

540 

Pennsylvania                                           

2,000 

2,730 

West  Virginia  

570 

1  ,000 

Southeastern  Ohio                                  

115 

110 

Kentucky               

400 

290 

Tennessee                                   

69 

Alabama 

50 

40 

2,504 

4,710 

The  strata  that  yield  oil  or  gas  in  the  Appalachian  field  (Fig.  92) 
include  those  of  the  Cambrian,  Silurian,  Ordovician,  Devonian, 
and  Carboniferous  systems.  The  pools  occur  generally  on  axes  and 
flanks  of  anticlines,  parallel  with  the  strike  of  the  Appalachian 
Mountains,  on  minor  terraces  or  other  structural  features  asso- 
ciated with  them,  and  in  water-free  synclines.  The  reservoir  rocks 
are  mainly  sandstones  or  conglomerate  layers.  An  exception  is 
the  Big  lime  (Greenbrier  limestone),  which  contains  oil  in  West 
Virginia. 

The  Paleozoic  rocks  of  the  region  are  mainly  shales,  .sand- 
stones, and  limestones.  The  general  structure  is  shown  by  Fig. 
93.  The  contour  interval  on  this  map  is  not  small  enough  to  show 
the  details  of  folding.  The  map  does  show,  however,  the  great 
Burning  Springs- Volcano  anticline,  in  western  West  Virginia. 
Unlike  the  other  minor  folds  of  the  geosyncline,  which  strike  north- 
east, the  Volcano  fold  strikes  nearly  north,  across  the  regional 
strike  of  the  country.  (See  also  Figs.  97  and  98.)  A  section  from 
eastern  Ontario  southward  to  West  Virginia  is  given  in  Fig.  94. 
The  strata  vary  in  character  so  that  a  section  taken  at  one  place 
differs  considerably  from  other  sections.  There  are,  however, 

/-  certain  persistent  and  fairly  constant  strata  that  can  be  correlated. 

)  The  Pittsburgh  coal  lies  near  the  surface  over  much  of  this  area. 

l  It  is  a  persistent  member  and  because  of  its  value  its  position  has 
been  determined  with  great  accuracy.  It  therefore  serves  as  a 
horizon  marker  and  a  key  rock  to  the  structure.  Below  the  Pitts- 
burgh coal  are  other  coals,  which  also  serve  as  keys  to  the  struc- 
ture. The  section  containing  the  coals  is  made  up  principally 


APPALACHIAN,  LIMA-IND.,  AND  MICH.  FIELDS  209 


of  sandstones,  shales,  and  limestones.  Another  horizon  marker 
is  the  Salt  sand,  which  is  the  top  of  the  Pottsville  formation. 
Below  the  Salt  sand  is  the  Big  lime.  The  Big  Injun  sand  lies 
below  the  Big  lime,  and  below  it  are  the  Gordon,  Elizabeth,  Brad- 
ford, and  other  sands.  A  section  of  the  rocks  is  shown  in  Fig.  95. 
Other  sections  are  given  on  pages  213  and  215. 

CORRELATIONS  IN  THE  APPALACHIAN  FIELD 
(After  Fuller;  Figures  Indicate  Thickness  in  Feet) 


Pennsylvania 
and  Northern 
West 

Southern 
West 
Virginia 

Kentucky 

Tennessee 

Alabama, 
Warrior 

Virginia 
(Rogersville 

(Buck- 
hannon 
Folio, 

(London 
Folio, 
Campbell) 

(Briceville 
Folio, 
Keith) 

Coal  Field 
(Birming- 
ham Folio, 

Clapp)     . 

Taff  and 
Brooks) 

Butts) 

Upper 

Dunkard, 

Permian 

barren 

1100 

Upper  pro- 

Mononga- 

Braxton, 

PHfsbi 

ductive 

hela,  400 

'     700 

Lower 
barren 

Conemaugh, 

Upshur, 
400 

measures 
(not 

Pennsyl- 

TVrS^ 

correlated), 

. 

vanian 

Lower  pro- 

Allegheny, 

Pugh, 

Lower  coal 

2500 

£ 

ductive 

300     , 

400 

measures, 
500 

S3 

V-        •  •  '     ,     __ 

| 

Conglom- 

Pottsville, 

Pickens, 

Lee, 

Lee, 

Pottsville, 

3 

erate 

^  ^p°v\ 

400 

1000 

1000 

2500 

Mauch 
Chunk, 

Canaan 
shale, 
600 

Pennington, 
100 

Pennington, 
300 

Pennington, 
200 

Mississip- 
pian 

7  iV 

Greenbrier, 
100 

Greenbrier 
First, 
350 

Newman, 
200 

Newman, 
700 

Greenbrier, 
200 

Pocono, 

Pocono, 

Waver  ly, 

*     600 

50 

350 

-J-i   -v  J  1}    x 

"^* 

Catskill, 

Hampshire, 

Chattanooga 

-500 

800 

shale, 

.* 

/"H%      4-4- 

Ot*      +4> 

Devonian 

Chemung 
«    and 

Jennings, 

shale, 
150 

shale, 
50 

(Frog  Moun- 
tain sand- 

Hamilton, 

800  + 

stone?) 

Total 

7450 

4500 

2300 

2050 

2925 

210 


GEOLOGY  OF  PETROLEUM 


tUAf 


IWIl 


111 


1    \ 


ill      -? 


\\\\ 


isr 


New  York,  Pennsylvania  and  West 
Virginia. — The  great  Appalachian  syncli- 
norium  is  about  800  miles  long.  It  is  over 
200  miles  wide  at  the  northeast  end  and  50 
miles  or  less  at  the  southwest  end.  The  syn- 
clinorium  embraces  many  minor  anticlines 
and  synclines,  which  are  of  considerable 
amplitude  in  the  eastern  part  of  the  field, 
near  the  mountains,  but  gradually  die  out  or 
become  flatter  toward  the  northwest.  Note- 
worthy folds  are  the  Burning  Springs- Vol- 
cano-Eureka  anticline  (Fig.  36,  p.  131),  the 
Wick  anticline,  the  Arches  Fork  anticline, 
and  the  Chestnut  Ridge  and  Laurel  Ridge 
anticlines.  In  southern  West  Virginia  the 
subordinate  folds  become  less  pronounced 
toward  the  northwest,  the  beds  rising  gradu- 
ally toward  the  west,  where  they  are  exposed 
at  the  Cincinnati  anticline  in  Ohio,  eastern 
Kentucky,  and  eastern  Tennessee.  As  a  rule 
the  dips  are  gentle,  commonly  less  than  3°. 
Locally  the  strata  dip  at  higher  angles,  and 
exceptionally,  as  on  the  flanks  of  the  Burn- 
ing Springs- Volcano  anticline,  the  dips  rise 
to  10°  or  20°  or  more.  In  New  York,  Penn- 
sylvania, West  Virginia,  and  Ohio  there  is 
very  little  faulting  in  the  oil  fields.  In 
eastern  Kentucky  and  Tennessee  faults  of, 
considerable  magnitude  are  present. 

Where  the  rocks  are  saturated  with  salt 
water,  as  a  general  rule  the  oil  and  gas  oc- 
cupy the  anticlines,  terraces,  or  domes,  and 
the  gas  rises  above  the  oil.  According  to 
Griswold  and  Munn,1  this  is  true  of  deposits 
in  the  Salt  sand  and  in  the  Big  Injun  sand 
below  it,  which  belongs  to  the  Pocono  of  the 

KJRISWOLD,  W.  T.,  and  MUNN,  W.  J.:  Geology 
of  Oil  and  Gas  Fields  in  Steubensville,  Burgettstown, 
and  Claysville  Quadrangles,  Ohio,  West  Virginia, and 
Pennsylvania.  U.  S.  Geol.  Survey  Bull.  318,  1907. 


APPALACHIAN,  LIMA-IND.,  AND  MICH.  FIELDS  211 


Mississippian.  The  still  lower  Catskill  sands  are  not  fully  satu- 
rated, and  some  of  them  are  dry.  The  oil  apparently  has  been  let 
down  from  the  higher  structural  positions  and  in  some  places  is 
held  up  on  the  flanks  of  synclines  by  water  that  remains  in  the 
beds.  (See  Fig.  63,  p.  154).  If  no  water  remains  the  oil  will  be  at 


AVERAGE  SECTION 

IN  BRIMtH  FIELDS. 

CENTRAL  OHIO 


AVERAGE  JfC7/0/V 
IN  SOUTHWESTERN  PEHSYL  VAHN/A 
A  SID  NORTHERN  WEtf  VIRGINIA 


AVERAGE  SECTIOli 

WHERE  THE  FORMATIONS  OUTCROP 
IH  EASTERN  WEST  VIR6IMA 


Fee?- 


100  toot  s 

bordcn  iancf 
Fourrh  jancf 


mil?  limestone 
ig  Injun  Sand 
/averley  shaln 
farea  s 
Red  rock 


Bedford  and 
Ohio  shales 


Romney  shale  g0oo 
Mcnferey 


Rockwoofl 
•formation 


Junioitci. 
•formation 

Martmsburq'' 
Shale 


14,000 

Shenorno/ocih 
lime&tone 

15,000 


FIG.  95. — Comparative  stratigraphic  columns  for  Ohio,  Pennsylvania  and 
West  Virginia.  (After  Clapp.) 

the  bottoms  of  the  folds.  The  water  content  of  the  reservoir  strata 
in  the  region  south  of  Pittsburgh  a  few  years  after  Griswold  and 
Munn's  examination  was  investigated  by  Reeves.1  The  Catskill, 
BEEVES,  FRANK:  Absence  of  Water  in  Sandstones  of  the  Appalachian  Oil 
Fields.  Econ.  Geology,  vol.  12,  pp.  254-278,  1917. 


212  GEOLOGY  OF  PETROLEUM 

which  is  a  terrestrial  phase  of  the  Devonian,  *  is  developed  over  a 
considerable  area.  It  is  a  series  of  red  shales  and  thin  reddish  or 
white  sandstones.  Eastward  along  the  outcrop,  the  formation  con- 
sists of  600  to  900  feet  of  alternating  layers  of  shale  and  sandstone, 
red  and  green,  which  are  unfossiliferous  and  in  places  sun-cracked 
and  ripple-marked.  The  shale  contains  about  6  per  cent  of  ferric 
oxide.  These  sands  are  not  saturated. 

Many  wells  in  this  field  produce  both  oil  and  gas,  and  some  pro- 
duce both  from  the  same  stratum.  In  many  wells  the  gas  carries 
considerable  gasoline.  In  1917,  according  to  Northrop,2  West 
Virginia  marketed  32,668,647  gallons  and  Pennsylvania  marketed 
13,826,250  gallons  of  gasoline  derived  from  natural  gas. 

Many  of  the  folds  yield  gas  only,  and  in  general  such  folds  lie 
east  of  the  petroleum-bearing  folds  and  nearer  to  the  Appalachian 
Mountains.  Where  dynamo-chemical  alteration  has  been  suf- 
ficient to  alter  the  coals  so  that  they  have  a  high  carbon  content, 
gas  only  is  produced.  This  relation  was  first  pointed  out  by  David 
White3  and  was  further  developed  by  Fuller.4  According  to 
Fuller  the  occurrence  of  65  to  70  per  cent  of  fixed  carbon  in  pure 
coals  establishes  a  sort  of  dead  line  as  regards  commercial  deposits 
of  oil  or  gas.  Where  coals  range  from  60  to  65  per  cent  of  fixed 
carbon,  gas  may  be  found  in  quantity,  but  little  commercial  oil. 
Where  coals  range  from  55  to  60  per  cent  of  fixed  carbon,  oils  are 
found  in  abundance,  with  abundant  gas.  In  the  west  part  of  the 
Appalachian  field  carbon  ratios  are  lower.  Some  of  the  oil  lies  east 
of  the  gas. 

The  first  serious  attempt  to  develop  the  petroleum  industry 
in  the  northern  Appalachian  region  resulted  from  the  drilling  of 
a  well  ai  Titusville,  Pennsylvania,  by  E.  L.  Drake  in  1859. 
Although  it  was  not  a  large  well,  there  was  a  sale  for  the  oil  and 
other  wells  were  drilled,  opening  many  oil  pools.  The  first  flowing 
well  or  gusher  was  one  sunk  near  Rouseville  in  1860,  and  several 
others  yielding  from  3,000  to  4,000  barrels  a  day  were  brought  in 

IBARRELL,  JOSEPH  :  The  Upper  Devonian  Delta  of  the  Appalachian  Geo- ; 
syncline.     Am.  Jour.  Sci.,  4th  ser.,  vol.  36,  pp.  429-472,  1918;  vol.  37,  pp. 
87-109,  225-253,  1914. 

NORTHROP,  J.  D.:  U.  S.  Geol.  Survey  Mineral  Resources,  1917,  part  2, 
p.  1119,  1919. 

3WniTE,  DAVID:  Some  Relations  in  Origin  Between  Coal  and  Petroleum. 
Washington  Acad.  Sci.  Jour.,  vol.  5,  pp.  189-212, 1915. 

DULLER,  M.  L.:  Geol.  Soc.  America  Bull.,  vol.  27,  p.  649,  1917. 


APPALACHIAN,  LIMA-IND.,  AND  MICH.  FIELDS  213 


Series 

Columnar 
section 

Thicknes 
(feet) 

Total 
(feot) 

Description 

• 

=^7"-  --.-:.  TTT.-~ 

0     ** 

Sg^rSSL^ 

Variegated  shales 

as 

w   a 

Dunkard 

U50 

U50 

and  gray  sandetones 
with  a  few  thin  coal 

a 

==5I===^E 

3 

Monongahela 
(Pittsburgh  coal  at  base  ) 

|    ^~:-~^ 

400 

1550 

Gray  sandstones,  gray 
shales,  limestones,  and 
coal  beds 

"3 

00        S 

Oonemaugh 

r^ZHl^ 

600 

2150 

Gray  or  brown  sandstones, 
gray  and  red  shales, 

and  coal  beds 

~     0 

Allegheny 

^^^.ll^l" 

250 

2400 

Gray  sandstones,  gray 
shales,  and  coal  beds 

5    * 
E 

Pottsville 

(Bait  Bands  of  West  Virginia) 

SCO 

2700 

Gray  sandktoucs,  and  shales, 
with  a  few  coal  beds 

° 

Mauch  Chunk 

(Cvntains  Maxton  Bund  of  West  Virginia 

^1^^^^^ 

250 

2950 

Red  shales  with  a  few  thin 
sandstones 

sg 

?Br!^h£#  WXe8t  Virginia^               / 

.J-i---^--'-^4'--'_-'ri4*r 

v    100 

3050 

Limestone 

Pocono 
(Big  Iniun  at  toj>;  L'erea 
Bund  at  base  } 

500 

3550 

Gray  sandstones  and 
gray  shales 

=^  -^rr=i^ 

Catskill 

E^^^=^^^ 

Brown  sandstones 

(Gordon  group  of  oil  Bauds) 

800 

4350 

and  red  shales 

Chemuag 

a 

•a 

(No  productive  sands 
iu  West  Virginia) 

^^=^^H^^ 

1500C?) 

5850 

Olive.  brown,  shales 
with  sandstones  lentils 

E3HZH-=I^^= 

Q 

^=^=^^r£:^^=: 

Gray  shales  with  sandstones 

(No  productive  sands 
in  West  Virginia) 

^-^^—  —  —  —  ^^_—  _^^__ 

Hamilton 

(No  productive  sands 
in  West  Virginia) 

room 

6650 
7350 

lentils 

Brown,  shales  with 
sandstone    lentils 

Marcallus  or  Komney 

Gas  In  Obio  and  Kentucky  ) 

300(?) 

7650 

"Brown,  or  blcck  bituminous 
shales  with  sandstone  lentils 

Onoiidaga"  limestone 
Oriskany                                 / 

7¥^¥^?- 

\     50C?) 

7700 
7850 

Dark  flinty  limestone 

d 

• 

Helderberg 
Salina,  and  Niagara 
(Big  lime  of  Ohio) 

i^-r>tT^ 

800(?) 

8C50 

Limestone 

3 

Clinton 

^^^_^E^=^ 

200(?) 

8S50 

Variegated  shales 

OQ 

Medina  white  suudstoue           , 

(Clinton  oil  Baud  Ol  ^utbern  Obio)    / 

=^^^^^^^ 

\     50(V) 

8900 

White  sandstone 

Medina  shales 

Martinsburg  or 
Cincinnati  shale 
(Contains  Hudson  (and  of  Kentucky) 

500(?) 
500(?) 

9400 
9900 

Bed  shales  and  thin 
sandstones  

Gray  shales  with  sandstone 
leutils 

o 

^  ^^^=-  ^=_  ==_= 

Black  shales  with  sandstone 

1 
•g 

^S=tE^^^^=^S 

300(?) 

10200 

leutils 

1 

0 

Trenton 
and 
other  limestones 

1200(?) 

moo 

Limestones 

of  northern  Obio) 

FIG. 


96.  —  Columnar  section  for  central  part  of  West  Virginia  oil  fields,  Marion 
and  surrounding  Counties.  (After  Reger.) 


214 


GEOLOGY  OF  PETROLEUM 


during  1861.  Development  in  this  region  thereafter  was  rapid, 
reaching  a  maximum  in  1891,  from  which  it  has  slowly  declined. 
The  oil  is  of  high  grade,  is  rich  in  lighter  derivatives,  has  a  paraffin 
base,  and  is  essentially  free  from  sulphur. 

The  most  productive  portion  of  the  Appalachian  field  lies  in 
New  York,  Pennsylvania,  and  West  Virginia.     Geologic  sections 


FIG.  97. — Map  showing  axes  of  folds  in  part  of   Appalachian  geosyncline. 
For  sections  along  lines  A-A',  etc.,  see  Fig.  98.     (Based  on  map  by  Reger.) 

for  Pennsylvania  and  West  Virginia  are  given  in  Fig.  95  (p.  211), 
and  for  the  central  part  of  the  West  Virginia  in  Fig.  96.  The 
trends  of  the  principal  folds  in  these  States  are  shown  in  Fig.  97, 
and  cross  sections  are  given  in  Fig.  98.  The  distribution  of  oil 
and  gas  pools  in  New  York  and  Pennsylvania  is  shown  by  Fig. 
99  and  in  West  Virginia  by  Fig.  100. 


APPALACHIAN,  LlMA-IND.,  AND  MICH.  FIELDS  215 

S 


Ridge  peneplain 
Plane  uf  main  drainage 
Big  lime  of  West  Virgin!* 
Big  Injun  sand 
Ber^a  sand 
Gordon  sand    ' 

OrUkanj  sandstone 
Uvlderberg,  Halloa  and  Nlagwm 
limestones  (  Big  lime  of  Ohio  ) 
Medina  ("Clinton")  sand 
Trenton  and  other  I 


Ridge  peneplain 

Big  lime  of  Wen  Virginia 

Hi,  Injun  sand 

Plane  uf  main  dralnag* 

Ben*  sand 

Gordon  Band 

Oriskaoy  sandstra* 
Helderberg,  Ualina  and  Niagara 
liueetunee  (  Big  lime  of  Ohio) 
Medina  ("Clinton)  sand 
Trentun  and  otUs  limestones 

S 


S*    P  ^    i  <* 


_i 

S  •** 


Big  Urn*  of  West  Virginia 
Bi«  lujun  sand 
Berea   a»nd 


Ridge  peneplain 
Plane  uf  main  dralnan 


Oriekany  sandstone 
Holderberg,  8alina  and  Niagara 
lime.tone«(Blj  lime  of  Ohio) 
Medina  ("CMuton)  eand 


RUge  peneplata 
Place  ot  main  dralnag* 
CJ--C-^  Big  lime  ot  We«t  Virglnl* 
Big  Injun  sand 
Beroa  eand 


Oriekmy 

Uelderbevg,  Ualina  and  Nlajmra 
\limcBtonei  (  Big  Iline  of  Chit  ) 

Medina  (  'Clinton')  cand 
Trootoc  and  otner  I 


Solid  lines  indicate  lands  determined  from  well  records 
DUtcd  liac*  indicate  supposed  position  of  deep  sands  as 
detvruiiucd  from  a  few  deep  wells  and  fruat  lutorrals  oa*t 
and  iicet  uf  Appalachian  basin 


satdstone 

Helderberg,  ballua  and  Ma.-ara 
(Big  lima  of  Ohio) 
^  Medina  ('  'Clinton")  Band 
Trenton  and  other  limestone* 


FIG.  98. — Cross-sections  showing  position  of  folds  in  part  of  Appalachian  geo- 
synclinc.  For  lines  of  sections,  see  Fig.  97.    (After  Reger.) 


216 


GEOLOGY  OF  PETROLEUM 


In  New  York  the  greater  part  of  the  oil  is  derived  from  the 
Bradford  sand,  in  the  Chemung  formation,  or  from  other  sands  not 
far  above  or  below  it.  Gas  is  produced  from  the  Corniferous  lime- 
stone of  the  lower  Devonian;  from  the  Guelph  limestone,  Niagara 


Gas 


Oil 


FIG.  99. — Map  of  oil  and  gas  producing  areas  of  northern  Appalachian  region. 

(After  Munn.} 

limestone,  and  Medina  sandstone  of  the  Silurian;  from  the  Trenton 
limestone  and  Lorraine  shale  of  the  Ordovician;  and  from  the  Pots- 
dam sandstone  of  the  Cambrian. 


APPALACHIAN,  LIMA-IND.,  AND  MICH.  FIELDS  217 

In  the  Pennsylvania- West  Virginia  area  oil  is  found  both  above 
and  below  the  Pittsburgh  coal  in  the  Pennsylvanian  series,  and  in 
the  Mississippian  and  Devonian.  Oil  is  produced  from  the  Kane 
sand,  in  the  Chemung,  3,770  feet  below  the  Pittsburgh  coal.  (See 
p.  219.)  Some  of  the  formations  that  produce  gas  in  New  York  will 


Off 


FIG.  100.  —  Map  showing  principle  oil-producing  areas  in  West  Virginia. 

probably  be  found  productive  in  Pennsylvania  and  West  Virginia, 
where  these  formations  lie  at  great  depth. 

The  principal  oil  horizons  in  the  Pennsylvanian  and  West  Vir- 
ginia districts  are  stated  on  pages  218-219. 


218  GEOLOGY  OF  PETROLEUM 

OIL  HORIZONS  OP  PENNSYLVANIA-WEST  VIRGINIA  DISTRICT** 
Carboniferous: 

Distance  Above  (  +) 

Pennsylvania!!:  °r  Below  ( — )  the 

Pittsburgh  Coal, 

Monongahela  formation  (Upper  Productive  measures) :  in  Feet 

Carroll  sand  (Uniontown  sandstone),  productive  in  West 

Virginia  only +    300 

Pittsburgh  coal  horizon. 
Conemaugh  formation  (Lower  Barren  measures) : 

Murphy,  Shallow,  Little  Dunkard,  or  First  Cow  Run  sand 

(Saltsburg  sandstone) -    200 

Big  Dunkard  or  Cow  Run  sand  (Mahoning  sandstone) -    500 

Allegheny  formation  (Lower  Productive  measures) : 

Second  Cow  Run  sand  (Freeport  sandstone) —    600 

Gas  sand -    800 

Pottsville  formation  (Salt  sand) : 

Johnson  Run  sand  (Homewood  sandstone) -    900 

Upper  Salt  sand  (Lower  Conoquenessing  sandstone) -    950 

Middle  Salt  sand  (Lower  Conoquenessing  sandstone) -1,050 

Lower  salt  (Sharon  conglomerate) -1,150 

Mississippian: 

Mauch  Chunk  formation:6 

Maxton  or  Cairo  sand  (of  West  Virginia) -1,200 

Greenbrier  limestone  (Big  lime) -1,250 

Pocono  formation  (Big  Injun  sand) : 

Keener  sand -1,300 

First,  Second,  and  Third  Pay  sands  (Top) -1,400 

Squaw  sand -1,450 

Wier  sand -1,500 

Upper  Gas  sand -1,550 

Berea  or  Thirty-foot  sand -1,750 

Murrysville  or  Butler  sand -1,800 

Gantz,  First,  or  Hundred-foot  sandc -1,850 

"FULLER,  M.  L.:  Appalachian  Oil  Fields.  Geol.  Soc.  America  Bull,  vol.  28,  p.  633,  1917. 
See  also  CLAPP,  F.  G.:  Outline  of  the  Geology  of  Natural  Gas  in  the  United  States.  Econ. 
Geology,  vol.  8,  pp.  520-521,  1913. 

^REGER  divides  the  Mississippian  into  Mauch  Chunk,  Greenbrier,  and  Pocono.     See  Fig.  96. 

TULLER  places  the  Upper  Gas,  Berea,  Butler,  and  Hundred-Foot  sands  in  the  Catskill. 
Following  recent  United  States  Geological  Survey  practice  here,  I  have  placed -them  in  the 
Mississippian.— (W.  H.  E.) 


APPALACHIAN,  LIMA-IND.,  AND  MICH.  FIELDS  219 

Devonian: 
Catskill  formation: 

Fifty-foot  sand -1,900 

Nineveh,  Thirty-foot,  or  Second  sand -2,000 

Gray,  Gordon  Stray,  or  Boulder  sand -2,100 

Gordon,  Third,  or  Campbells  Run  (?)  sand -2,150 

Fourth  sand  (Gordon  of  West  Virginia?) -2,200 

Fifth  sand  (McDonald  of  West  Virginia?) -2,250 

Bayard  sand -2,400 

Chemung  formation: 

Elizabeth  or  Sixth  sand -2,600 

I    Warren  First  sand -2,700 

Warren  Second  sand -2,800 

Tiona  sand -2,900 

Speechley  sand -3,000 

Balltown  or  Cherry  Grove  sand. -3,120 

Sheffield  or  Cooper  sand r t . . .  -3,320 

Bradford  sand -3,430 

Second  Bradford  sand . . ./ -3,480 

Elk  sand -3,650 

Kane  sand -3,770 

In  southwestern  Pennsylvania  and  northwestern  West  Virginia 
the  sands  in  the  Upper  Devonian  contain  much  oil  and  gas.  These 
sands  constitute  the  Venango  oil-sand  group,  which  is  an  important 
oil-bearing  series  in  southwestern  Pennsylvania.  Below  the  Cats- 
kin  the  Corniferous  limestone  is  found  at  great  depths  in  this  field. 
A  j  well  near  McDonald,  Pennsylvania,1  penetrated  the  Lower 
Devonian  limestone.  At  a  depth  of  6,260  feet  a  sandstone,  pos- 
sibly the  Oriskany,  was  encountered  which  contained  concentrated 
brine.  Reeves  states  that  the  Catskill  sands  are  free  from  salt 
water  because  they  were  laid  down  under  arid  conditions.  Accord- 
irig  to  Reeves  they  have  never  been  saturated  with  water,  although 
the  marine  sediments  both  above  and  below  are  saturated  with 
brine. 

In  many  of  the  oil  sands  the  oil  and  gas  occur  in  pockets,  where 
the  sands  are  coarser  (p.  115).  In  the  Carboniferous  rocks,  which 
are  generally  saturated  with  water,  the  oil  at  many  places  is  on 
high  parts  of  the  folds.  A  well-known  example  is  the  Volcano 
dome  of  the  Burning  Springs- Volcano-Eureka  anticline  in  West 
Virginia. 

WHITE,  I.  C. :  Note  on  a  Very  Deep  Well  Near  McDonald,  Pennsylvania. 
Geol.  Soc.  America  Bull.,  vol.  24,  pp.  275-282,  1913. 


220 


GEOLOGY  OF  PETROLEUM 


The  occurrence  of  oil  and  gas  on  anticlinal  noses  and  terraces 
has  been  noted. 

Because  of  its  great  gas  production  (see  p.  142),  extensions  east- 
ward of  the  "Clinton"  sand  have  aroused  much  interest.  The 
sand  dips  eastward  from  central  Ohio  at  a  low  angle  and  rises  again 
toward  the  west  front  of  the  Appalachian  Mountains.  As  stated 


FIG.  101. — Map  showing  location  of  certain  wells  and,  by  contours,  the 
approximate  thickness  of  the  Upper  Devonian  in  part  of  the  Appalachian  oil 
field.  (Redrawn  from  a  map  by  I.  C.  White.) 

by  Bownocker,  the  small  oil  pools  found  in  the  sand  contain  no 
water,  and  he  suggests  that  they  may  occur  in  small  shallow  basins 
rather  than  on  anticlines.  It  is  believed  by  some  that  large 


APPALACHIAN,  LIMA-IND.,  AND  MICH.  FIELDS  221 


deposits  of  oil  will  be  found  below  the  gas  in  the  deeper  part  of  the 
basin.  Many  deep  wells  have  been  sunk  in  the  Appalachian 
basin,  but  in  the  central  part  of  the  basin  none  of  them  have  pene- 
trated the  "Clinton"  sand.  These  wells  supply  information  con- 
cerning the  strata  in  a  large  part  of  the  Appalachian  field. 

Fig.  101,  after  White,1  is  a  sketch  showing  the  thickness  of 
the  Upper  Devonian.  The  strata  are  measured  between  the  Berea 
sand  and  the  top  of  the  Corniferous  limestone.  The  Upper  De- 
vonian shales  are  only  500  feet  thick  in  the  region  near  Columbus, 
Ohio,  but  their  thickness  becomes  very  great  toward  the  central 
part  of  the  basin.  At  the  Martha  O.  Goff  well,  in  northern  West 
Virginia,  which  is  one  of  the  deepest  wells  in  the  world,  the  Upper 
Devonian  is  nearly  6,000  feet  thick.  The  formations  encountered 
in  this  well,  below  the  Pittsburgh  coal,  which  before  erosion  was 
not  far  above  the  casing  head,  are  shown  in  the  following  table : 


Thickness 


Depth 


Pittsburgh  coal,  base  of  Monongahela  series. 
Conemaugh  series 600' 


Allegheny 290 

Pottsville 260 

Mauch  Chunk 260' 

Mountain  (Greenbrier)  lime- 
stone   Go 

Big  Injun,  Squaw,  and  Berea 

sand  group 265 

Catskill,  containing  Venango 
oil  sand  group,  to  base  of 

Bayard  oil  sand 770' 

Chemung  shales,  containing 
Elizabeth,  Speechley,  Brad- 
ford (Benson)  and  Kane  oil 

sands 2.190 

Portage  beds 1 ,207 

Genesee  slate 288 

Hamilton  and  Marcellus 1  ,368 

Corniferous  limestone  to  present  bottom . 


Pennsylvanian 


Mississippian 


Feet 

1  ,150 
590 


Feet 
1  ,150 

1,740 


Upper  Devonian 
shales 


5,823 


23 


7,563 


7,586 


,  I.  C. :  Discussion  of  the  Records  of  Some  Very  Deep  Wells  in  the 
Appalachian  Oil  Fields  of  Pennsylvania,  Ohio  and  West  Virginia.  West  Vir- 
ginia Geol.  Survey  County  Repts.,  Barbour  and  Upshur  Counties,  pp.  xxv-lxv, 
1918. 


222  GEOLOGY  OF  PETROLEUM 

The  record  of  the  well1  is  stated  l>elow:  Feet    " 

Native  coal  (Elk  Lick) 83-     86 

Little  Dunkard  sand 170-    186 

Big  Dunkard  sand , 305-    336 

Gas  sand 436-    446 

First  Salt  sand 690-   815 

Second  Salt  sand 860-   880 

Maxton  sand 1,025-1,040 

Little  lime 1,183-1,194 

Pencil  cave 1,194-1,210 

Big  lime;  gas  at  1,253  feet 1,210-1,275 

Big  Injun  sand;  water  at  1,304  feet 1,275-1,394 

Squaw  sand 1,410-1,428 

Berea  sand 1,512-1,540 

Gantz  sand  consolidated  with  Fifty-foot 

Fifty-foot  sand;  gas  at  1,749  and  1,757  feet 1,748-1,885 

Thirty-foot  sand 1,900-1,980 

Gordon  Stray  sand 2,090-2,097 

Gordon  sand 2,130-2,142 

Fourth  sand None 

Fifth  sand None 

Bayard  sand 2,300-2,310 

Slate  shells 2,310-2,830 

Hard  lime 2,830-2,893 

Slate  and  lime  shells '  .  2,892-3,125 

Hard  lime 3,125-3,145 

Slate  shells 3,145-3,222 

Hard  lime 3,222-3,240 

Slate  shells 3,240-3,480 

Hard  sand \ 3,480-3,505 

Slate 3,505-4,166 

Lime  shells  (Benson  sand);  with  puff  of  air  (gas) 4,166-4,167 

Slate 4,167-4,425 

Lime 4,425-4,500 

Slate  and  shells 4,500-4,790 

Lime 4,790-4,850 

Slate  shells 4,850-5,200 

Slate  shells  at 5,700 

Slate  shells  at 5,775 

Dark  slate 5,840-5,995 

Lime  shells 5,995-5,998 

Dark  slate 5,998-6,210 

Light  slate 6,210-6,235 

Lime 6,235-6,265 

Dark  slate 6,265-6,272 

Lime 6,272-6,280 

,  I.  C. :  Op.  tit.,  pp.  Ivi-lviii. 


APPALACHIAN,  LIMA-IND.,  AND  MICH.  FIELDS  223 

Dark  slate 6,280-6,294 

Lime 6,294-6,304 

Dark  slate 6,304-6,318 

Lime..  6,318-6,330 

Dark  slate 6,330-6,360 

Lime 6,360-6,380 

Dark  slate 6,380-6,385 

Lime 6,385-6,395 

Dark  slate 6,395-6,420 

Lime 6,420-6,426 

Dark  slate 6,426-6,438 

Lime 6,438-6,447 

Dark  slate 6,447-6,465 

Lime 6,465-6,470 

Dark  slate 6,470-6,500 

Blackslate. 6,500-6,505 

Black  lime.  . 6,505-6,510 

Black  slate 6,510-6,532 

Dark  slate 6,532-6,580 

Dark  slate 6,580-6,625 

Hard  shells 6,625-6,627 

Brown  shale 6,627-6,640 

Hard  shells .^ 6,640-6,645 

Black  slate 6,645-6,660 

Black  shale 6,660-6,676 

Black  sand 6,676-6,680 

Hard  lime 6,680-6,690 

Dark  slate 6,690-6,714 

Dark  lime 6,714-6,747 

Hard  shell 6,747-6,750 

Slate '.  6,750-6,755 

Dark  slate 6,755-6,775 

Hard  sand  shells 6,775-6,780 

Black  shale 6,780-6,800 

Black  slate 6,800-6,823 

Hard  lime 6,823-6,865 

Slate  and  shells 6,865-6,950 

Hard  lime 6,950-7,057 

Lime  shells 7,057-7,069 

Hard  sand 7,069-7,071 

Hard  lime 7,069-7,075 

Lime 7,081-7,093 

Hard  lime 7,093-7,097 

Hard  lime 7,097-7,110 

Slate  and  shells 7,110-7,150 

Slate 7,150-7,160 

Hard  lime 7,160-7,162 


224 


GEOLOGY  OF  PETROLEUM 


Lime  shells 7,162-7,176 

Gritty  shells 7,176-7,190 

Slate 7,190-7,225 

Slate 7,225-7,232 

Hard  shell 7,232-7,245 

Black  slate 7,245-7,251 

Slate  and  shells 7,251-7,256 

Hard  lime 7,256-7,261 

Dark  hard  lime 7,261-7,266 

Black  slate 7,266-7,280 

Hard  shells 7,280-7,282 

Slate 7,282-7,290 

Soft  slate 7,290-7,295 

Soft  black  slate 7,295-7,300 

Black  slate 7,300-7,345 

Gritty  lime 7,345-7,363 

Hard  flinty  limestone,  Corniferous,  to  bottom.  . 7,363-7,386 

The  R.  A.  Geary  well  at  McDonald,  Pennsylvania,  west  of  Pitts- 
burgh, was  described  by  White1  in  1913.  The  record  is  sum- 
marized as  follows,  beginning  at  the  base  of  the  Pittsburgh  coal, 
the  horizon  of  which  is  estimated  to  be  130  feet  above  the  derrick 
floor: 


Thickness 

Depth 

Conemaugh  Bfries       .    ...               580 

Pennsy  1  vanian 

Mississippian 

:>up),  Chemurg, 
Is  

Feet 
1,080 

672 

4,386 
37 
270 
385 
340 
208 

Feet 
1,080 

1,752 

6,138 
6,175 
6,445 
6,830 
7,170 
7,378 

Allegheny  series                                 284 

Pottsville  series  216 

Mauch  Chunk  3' 

Big  lime  (Mountain,  Greenbrier).   29 
Big  Injun,  Squaw,  and  Berea  sands.  640 
Catskill,  (including  Venango  oil-sand  gr< 
Portage,  Hamilton,  and  Marcellus  be< 
Corniferous  limestone  

Oriskany  sandstone 

Helderberg.          

Salina  salt  series 

Salina  shales  and  Niagara  (Clinton?)  .  . 

,  I.  C. :  Note  on  a  Very  Deep  Well  Near  McDonald,  Pennsylvania, 
Geol.  Soc.  America  Bull,  vol.  24,  pp.  275-282,  1913. 


APPALACHIAN,  LIMA-IND.,  AND  MICH.  FIELDS  225 

The  Upper  Devonian  is  4,386  feet  thick,  which  is  somewhat 
thinner  than  in  the  Goff  well. 

Eastern  Ohio. — In  Ohio  there  are  three  fields  that  produce  oil 
or  gas  or  both.1  In  an  extension  of  the  Appalachian  field  in 
eastern  Ohio  the  petroliferous  strata  developed  in  western  Penn- 
sylvania and  West  Virginia  are  present.  West  of  this  belt  is  the 
"Clinton"  sand  field,  which  yields  much  gas.  Still  farther  west 
and  extending  into  Indiana  is  the  great  Lima-Indiana  field,  in 
which  oil  and  gas  are  derived  from  the  Trenton  limestone.  This 
is  not  classed  with  the  Appalachian  oil  fields  but  is  related  to  the 
Cincinnati  arch,  which  lies  west  of  the  Appalachian  basin. 

PRINCIPAL  OIL-PRODUCING  ROCKS  IN  OHIO  AND  INDIANA 

(After  Bownocker) 

( Mitchell  sand  (Ohio). 

Pennsylvania!! .  .  .  <  Macksburg  140-ft.,  or  first  Cow  Run  sand  (Ohio). 
[Macksburg  500-ft.  sand  (Ohio). 


Mississippian . 


Huron  sandstone  (Indiana). 
Keener  sand  (Ohio). 
Big  Injun  sand  (Ohio). 


Berea  sand  (Ohio). 

Devonian Corniferous  limestone  (Indiana). 

Silurian "Clinton"  sand  (Ohio). 

Ordovician Trenton  limestone  (Ohio  and  Indiana). 

In  eastern  and  southeastern  Ohio  oil  and  gas  are  found  in  low 
folds  in  Pennsylvanian  and  Mississippian  rocks.  The  producing 
counties  extend  almost  across  the  eastern  part  of  the  State.  Mon- 
roe and  Washington  Counties  have  been  the  largest  producers. 
The  pools  are  numerous,  but  most  of  them  are  small,  not  more 
than  two  or  three  of  them  including  more  than  ten  square  miles. 
Thousands  of  wells  have  been  drilled.  So  many  tests  have  been 
made  that  the  chances  of  discovering  large  reservoirs  are  slight, 
and,  according  to  Bownocker,  the  production  of  5,586,433  barrels 
in  1903  will  probably  stand  as  the  maximum. 

BOWNOCKER,  J.  A. :  Petroleum  in  Ohio  and  Indiana.  Geol.  Soc.  America 
Bull,  vol.  28,  pp.  667-57G,  1917. 


226 


GEOLOGY  OF  PETROLEUM 


GENERALIZED  SECTION  OP  CARBONIFEROUS  FORMATIONS  IN  EASTERN  OHIO 
(After  Mills  and  Wells) 


1 

CO 

g 

1 

Group  or 
Formation 

Thick- 
ness 
(Feet) 

Character 

Driller's  Description 

« 

a 

Bj 

1 

Washington  f  or- 
mation.a 

400 

Nonpersistent  sandstone  members 
with  shale  and  clay  of  reddish- 
brown  color.  A  few  thin  beds 
of  coal  and  limestone  in  lower 
portion.  " 

_> 
1 

a 

33 

•a 

a 

'i 
'S 

3 

Monongahela 
formation. 

255-275 

Limestone,  shale,  and  a  little  sand- 
stone. Contains  the  Pitts- 
burgh, Pomeroy,  Meigs  Creek, 
Uniontown,  and  Waynesburg 
coal  beds,  all  of  more  or  less  value 
in  the  Woodsfield  quadrangle. 

Conemaugh  for- 
mation. 

460-475 

Irregular  members  grading  into 
shales,  commonly  of  reddish- 
brown  or  variegated  colors. 
Upper  and  lower  Pittsburgh 
limestone  members  near  top; 
Ames  and  Cambridge  limestone 
members  a  little  below  middle. 
Mahoning  sandstone  member  at 
the  base,  locally  productive  of 
oil. 

Includes  First  Cow 
Run,  Buell  Run,  and 
Mahoning  sands. 

Allegheny  for- 
mation. 

250-265 

Sandstone,  shale,  and  important 
clay  and  coal  beds,  including  the 
Lower  Kittanning,  Middle  Kit- 
tanning,  and  Lower  and  Upper 
Freeport. 

Includes  Peeker, 
Macksburg  500-foot, 
and  Second  Cow 
Run  oil  sands  named 
in  descending  order. 

Pottsville  for- 
mation. 

155-170 

Consists  largely  of  sandstone  and 
conglomerate,  which  rest  with 
uneven  contact  on  the  eroded 
surface  of  the  Mississippian 
beds.  The  sandstone  is  gen- 
erally divided  into  several  parts 
by  beds  of  clay  shale,  and  coals 
also  are  locally  present. 

Includes  Maxton  sand. 

Maxville  lime- 
stone. 

-U  nconf  ormity 

Logan  forma- 
tion. 

0-100 

Dark-gray  and  bluish  to  light-gray 
limestone  with  interbedded  shale 
and  fine-grained  sandstone. 

Big  lime;  includes  Big 
lime  sand. 

25-100 

Consists  of  sandstone,  the  Keener 
sand,  interbedded  with  shale;  a 
valuable  source  of  oil  and  gas 

[ncludes  Keener  oi 
sand. 

Black  Hand  for- 
mation. 

75-175 

Coarse  sandstone  interbedded 
with  and  grading  laterally  into 
sandy  shale. 

Probably  includes  Big 
Injun  and  Squaw  oil 
sands. 

Cuyahoga  for- 
mation. 

350-450? 

Mostly  sandy  shale  in  lower  part, 
with  a  few  beds  of  shaly  sand- 
stone. 

Includes  Welsh  oil 
sand. 

Sunbury  shale. 

25-40 

Dark  carbonaceous  shale. 

Black  shale. 

Berea    sand- 
stone. 

0-40 

Berea  sand,  consisting  of  coarse  to 
fine-grained  gray  to  white  sand- 
stone. Lenticular  in  the  Woods- 
field  and  Summerfield  quad- 
rangles. Unconformity  at  base. 

Berea  oil  and  gas  sand. 

°At  places  in  eastern  Ohio  the  Greene  formation  of  the  Permian  overlies  the  Washington. 


APPALACHIAN,  LIMA-IND.,  AND  MICH.  FIELDS  227 


GENERALIZED  SECTION  OF  OLDER  PALEOZOIC  FORMATIONS  IN  EASTERN  OHIO 

(After  Rogers) 


System 

Group  or 
Formation 

Thick- 
ness 
(Feet) 

Character 

Driller's 
Description 

Devonian  or 
Carbonifer- 
ous. 

Bedford  shale. 

20-40? 

Mottled  gray,  reddish,  and 
brownish  shale. 

Ohio  shale, 
1  ,100-3,000 
feet,  usually 
treated  as  a 
unit  in  south- 
ern Ohio. 

Devonian  

Unconformity. 
Silurian. 

Ohio  shale  group 

Cleveland  shale. 

50-120 

Massive  hard  black  bituminous, 
with  a  few  bluish  layers  in 
lower  portion. 

Chagrin  shale. 

850-1  ,200 

Soft  bluish-gray  clay  shale, 
with  some  concretionary 
layers. 

Huron  shale. 

Black  and  bluish  shale  in  upper 
and  lower  portions,  with  a 
band  of  gray  shale  near 
middle. 

Olentangy?  shale. 

80 

Gray  calcareous  shale. 

Delaware  lime- 
stone. 

500-700 

Blue  and  gray  limestone,  be- 
coming dolomitic  in  lower 
part.  Contains  a  30  to  50- 
foot  bed  of  white  quartz 
sandstone,  350  to  450  feet 
below  top. 

Big  lime;  i  n- 
cludes  New- 
burg  sand  and 
some  "stray" 
sands  in  lower 
300  feet,  490- 
1  ,825  feet. 

Columbus  lime- 
stone. 

Monroe  formation. 

3alina     formation. 

400-600 

Shale,  dolomite,  anhydrite  or 
gypsum,  and  rock  salt. 

Niagara  limestone. 

400-600 

Dolomite  and  limestone. 

'Clinton"  forma- 
tion. 

150-250 

Crystalline  limestone  of  various 
light  colors;  calcareous  shale 
and  thin-bedded  limestone, 
with  sandstone  layer  in  lower 
part. 

Includes  Little 
lime,  75-150 
feet. 

'Clinton"  sand, 
0-60  feet. 

25-75  feet. 

Medina  shale. 

400-300 

[led  clay  shale,  with  thin  layers 
of  sandstone. 

Medina  red 
rock. 

Ordovician.  .  .  . 

Shale  and  limestone 
of  Cincinnatian 
age. 

750-1  ,250 

Dark  shale,  with  thin  layers  of 
limestone,  especially  in  upper 
part. 

Slate  and  shells. 

Trenton    (?)    lime- 
stone. 

(?) 

Limestone. 

Trenton  lime. 

228  GEOLOGY  OF  PETROLEUM 

One  of  the  most  persistent  sands  is  the  Berea,  *  which  lies  near 
the  lower  part  of  the  Mississippian,  below  the  Sunbury  shale  and 
above  the  Bedford  shale.  The  Berea  yields  gas  or  oil  in  several 
counties;  its  outcrop  is  practically  continuous,  and  it  is  generally 
penetrated  wherever  the  drilling  is  carried  deep  enough.  Accumu- 
lations of  oil  and  gas,  as  stated  by  Panyity,  are  found  principally 
where  the  sand  thins  out  up  the  dip.  (See  p.  145.) 

In  the  Woodsfield  quadrangle,  which  includes  parts  of  Belmont, 
Monroe,  Noble,  and  Guernsey  Counties,  2  the  rocks  at  the  surface 
are  of  Pennsylvanian  and  Permian  age  and  include  in  ascending 
order  the  Conemaugh,  Monongahela,  and  Washington  formations. 
The  dip  or  slope  of  the  beds  is  in  general  southeastward.  The 
most  noteworthy  productive  sands,  named  in  descending  order, 
are  the  so-called  Cow  Run,  Big  lime,  Keener^  Big  Injun,  and  Berea. 
In  the  Barnesville  oil  and  gas  field,  in  the  northwestern  part  of  the 
Woodsfield  quadrangle,  the  gas  occupies  the  high  portion  of  the 
anticlinal  fold  and  is  flanked  by  an  oil-producing  belt  a  little  lower 
on  the  slope.  The  water  table  in  the  Berea  sand  is  of  local  extent 
and  probably  has  no  relation  to  water  tables  in  the  same  sand  in 
other  areas  to  the  west  and  north.  The  partial  saturation  in  this 
area  does  not  signify  that  the  quantity  of  salt  water  becomes  less 
as  the  oil  sand  is  followed  up  the  dip.  On  the  contrary,  great 
quantities  of  salt  water  and  also  some  oil  are  derived  from  the 
Berea  all  the  way  from  the  Woodsfield  quadrangle  northwestward 
to  Wooster  and  beyond,  where  the  sand  is  only  a  little  below  the 
surface.3  The  relations  of  accumulation  to  sands  and  water  con- 
ditions, according  to  Condit,  are  varied  and  uncertain,  although 
the  productive  belts  in  general  follow  structural  contours. 

The  Wooster  region,  in  Wayne  County,  has  recently  been 
described  by  Bonine.4  The  Wooster  field  is  a  little  west  of  the 
outcrops  of  the  Pottsville  and  Allegheny  formations  (Carbonifer- 
ous), which  mark  the  northwestern  limit  of  the  Appalachian  coal 
basin.  The  rocks  have  a  general  dip  to  the  east  and  southeast  of 


,  L.  S.  :  Lithology  of  the  Berea  Sand  in  Southeastern  Ohio,  and  Its 
Effect  on  Production.     Am.  Inst.  Min.  Eng.  Bull.  140,  pp.  1317-1320,  1917. 

2CoNDiT,  D.  D.  :  Structure  of  the  Berea  Oil  Sand  in  the  Woodsfield  Quad- 
rangle, Ohio.     U.  S.  Geol.  Survey  Bull  621,  p.  233,  1915. 
•    »CONDIT,  D.  D.:  Op.  tit.,  pp.  245-246. 

4BoNiNE,  C.  A.:  Anticlines  in  the  "Clinton"  Sand  Near  Wooster,  Wayne 
County,  Ohio.     U.  S.  Geol.  Survey  Bull  621,  p.  95,  1915. 


APPALACHIAN,  LIMA-IND.,  AND  MICH.  FIELDS  229 

about  50  feet  to  the  mile.  This  dip  has  been  flattened  in  many 
places,  producing  structural  terraces.  Cross  folding  of  a  more  or 
less  intense  character  has  likewise  taken  place,  producing  folds  at 
right  angles  to  the  strike  of  the  formations.  These  folds  are  especi- 
ally pronounced  in  the  "Clinton"  sand  and  exist  in  a  modified  form 
in  the  Berea  sandstone.  The  surface  rocks  near  Wooster'are  not 
well  exposed,  and  consequently  it  is  difficult  to  determine  whether 
or  not  they  are  similar  in  structure. 

The  principal  structural  feature  of  the  gas  field  is  the  steeply 
pitching  anticline  west  and  southwest  of  Wooster,  along  the  crest 
and  sides  of  which  the  gas  has  accumulated. 

The  "Clinton"  gas  field1  is  one  of  the  largest  sources  of  natural 
gas  in  the  world.  In  1912  the  output  of  natural  gas  in  Ohio  ex- 
ceeded 56,000,000,000  cubic  feet,  and  in  1913  it  was  50,300,000,000 
cubic  feet.  The  value  of  the  output  in  1912  was  nearly  $12,000,000 
and  probably  90  per  cent  of  this  came  from  the  "Clinton"  sand. 
jjThe  name  "Clinton"  was  early  applied  to  the  gas  sand  at  Lan- 
1  caster,  Ohio,  and  it  became  well  established.  However,  it  was 
shown  by  Bownocker  that  the  gas-bearing  rock  lies  below  the  true 
Clinton  formation  and  is  of  Medina  age.  Natural  gas  was  dis- 
covered in  this  rock  at  Lancaster  in  1887,  and  the  field  has  been 
developed  so  that  it  now  extends  from  the  shore  of  Lake  Erie 
southward  almost  to  the  Ohio  River. 

The  position  of  the  "Clinton"  sand  in  deep  wells  is  easily  deter- 
mined by  the  great  Devonian  and  Silurian  limestones  (Big  lime), 
the  base  of  which  usually  lies  from  90  to  150  feet  above  the  sand. 
The  sand  itself  lies  between  shales.  The  "Clinton"  sand  is  not 
everywhere  present  in  this  region.  It  is  not  found  in  the  western 
half  of  Ohio.  The  sand  thins  out  in  the  longitude  of  Columbus, 
and  farther  west  its  horizon  is  occupied  by  shales.  The  sand  along 
its  western  border — that  is,  from  Cleveland  to  Lorain  and  thence 
south  to  the  Ohio  River — is  patchy  and  uncertain.  The  sand  is 
thus  a  lens,  or  series  of  lenses,  embedded  in  fine  shales 
(see  p.  143). 

The  thickness  of  the  "Clinton"  varies.  Its  maximum  is  placed 
by  Bownocker  at  about  100  feet,  but  measurements  of  half  that 
amount  are  known,  and  the  usual  thickness  ranges  from  10  to  40 

'BOWNOCKER,  J.  A.:  Natural  Gas  in  Ohio.  Cleveland  Engineering  Soc. 
Bull,  vol.  8,  No.  5,  pp.  322-332,  1916. 


230 


GEOLOGY  OF  PETROLEUM 


feet.  Its  texture  is  rather  coarse.  The  rock  commonly  has  a 
light  gray  color,  but  in  places  it  is  brick-red.  At  many  places  it  is 
impervious  and  barren. 

The  initial  pressure  in  the  field  was  everywhere  high  and 
increases  with  the  depth.  In  the  southern  part  of  the  field  it  was 
about  700  pounds  to  the  square  inch ;  between  Newark  and  Mount 
Vernon,  750  pounds;  in  Ashland  County,  1,200  pounds;  and  in 
Cuyahoga  County  1,050  pounds.  The  greatest  pressure  near 
Butler,  Richland  County,  was  1,260  pounds. 

The  first  large  well  in  the  "Clinton"  was  the  Mithoff,  at  Lan- 
caster, which  yielded  initially  at  the  rate  of  12,000,000  cubic  feet 
a  day.  From  Newark  to  Mount  Vernon  the  largest  wells  yielded 
about  12,000,000  cubic  feet,  and  in  Ashland  County  13,000,000 
cubic  feet.  A  well  drilled  in  Congress  Township,  Wayne  County, 
early  in  September,  1915,  started  flowing  at  the  rate  of  22,000,000 
cubic  feet  a  day.  Many  wells  flow  from  3,000,000  to  5,000,000 
cubic  feet. 

Wells  in  the  "Clinton"  are  long  lived,  for  gas  wells,  as  a  result  of 
the  porous  nature  of  the  rocks  and  the  high  pressure  of  the  gas. 
Difficulties  in  drilling  are  encountered  because  of  brine  in  the  Big 
lime,  which  lies  a  short  distance  above  the  gas  rock.  This  brine 
has  done  great  damage  to  many  wells. 

RECORD  OP  A  "CLINTON"  OIL,  WELL  NEAR  BREMEN,  FAIRFIELD  COUNTY,  OHIO 

(After  Bownocker) 


Thickness 

I 

)epth 

Mantle  rock 

Feet 
49 

Feet 

49 

Cuyahoga  and  Sunbury  sandstone  and  shales.  .  . 
Berea  sandstone                                          

626 
35 

675 
710 

Bedford  and  Ohio  shales 

975 

1 

685 

Devonian  limestone        .              .              

50 

1 

,735 

IMonroe  limestone 

275 

2 

,010 

Silurian  Niagara  limestone         

360 

?, 

,370 

Clinton  limestone 

95 

?, 

,465 

Shales 

120 

2 

,585 

"Clinton"  sand  

34 

2 

,619 

Bottom  of  well                  *  

?, 

,620 

APPALACHIAN,  LIMA-IND.,  AND  MICH.  FIELDS  231 

Many  wells  have  been  drilled  for  oil  in  the  "Clinton."  Oil  in 
paying  quantities  was  first  obtained  in  this  stratum  in  1899,  but 
no  large  pools  were  found  until  1907,  when  the  reservoir  in  eastern 
Fairfield  County  was  discovered. 1 

The  oil,  which  has  a  density  ranging  from  35°  to  46°  Baume, 
differs  in  no  important  way  from  the  light  oils  of  Pennsylvania  and 
West  Virginia.  Its  occurrence  is  uncommon  in  Ohio,  in  that  it 
appears  to  be  free  from  water.  From  this  fact  the  conclusion  is 
reached  that  the  oil  lies  in  shallow  basins  rather  than  on  the  slopes 
of  anticlines.  The  production  of  the  "Clinton"  sand  at  its  maxi- 
mum was  about  1,300,000  barrels  a  year.2 

References  on  Appalachian  Fields  in  New  York,  Pennsylvania,  West  Virginia 

and  Ohio 

ASHBURNER,  C.  A. :  The  Production  and  Exhaustion  of  the  Oil  Regions  of 
Pennsylvania  and  New  York.  Am.  Inst.  Min.  Eng.  Trans.,  vol.  14,  pp.  419- 
427,  1886. 

—  The  Geology  of  Natural  Gas.     Idem,  pp.  428-438. 

ASHLEY,  G.  H.,  and  CAMPBELL,  M.  R.:  Geologic  Structure  of  the  Punx- 
sutawney,  Curwensville,  Houtzdale,  Barnesboro,  and  Patton  Quadrangles, 
Central  Pennsylvania.  U.  S.  Geol.  Survey  Bull.  531,  pp.  69-89,  1913. 

BONINE,  C.  A.:  Anticlines  in  the  Clinton  Sand  Near  Wooster,  Wayne 
County,  Ohio.  U.  S.  Geol.  Survey  Bull.  621,  pp.  87-98,  1916. 

BOWNOCKER,  J.  A. :  Petroleum  in  Ohio  and  Indiana.  Geol.  Soc.  America 
Bull.,  vol.  28,  pp.  667-676,  1917. 

—  Petroleum  and  Natural  Gas  in  Ohio.     Ohio  Geol.  Survey,  4th 
ser.,  Bull  1,  1903. 

—  The  Bremen  Oil  Field.     Idem,  Bull.  12,  1910. 

The  Clinton  Sand.     Econ.  Geology,  vol.  6,  p.  37,  1911. 

BUTTS,  CHARLES:  Economic  Geology  of  the  Kittanning  and  Rural  Valley 
Quadrangles,  Pennsylvania.  U.  S  Geol.  Survey  Bull.  279,  pp.  1-198,  1906. 

U.  S.  Geol.  Survey  Geol.  Atlas,  Rural  Valley  folio  (No.  125),  1905. 
U.  S.  Geol.  Survey  Geol.  Atlas,  Warren  folio  (No.  172),  1910. 
and  LEVERETT,  FRANK.     U.  S.  Geol.  Survey  Geol.  Atlas,  Kittan- 
ning folio  (No.  115),  1904. 

CAMPBELL,  M.  R.:  U.  S.  Geol.  Survey  Geol.  Atlas,  Masontown-Uniontown 
folio  (No.  82),  1902. 

U.  S.  Geol.  Survey  Geol.  Atlas,  Brownsville-Connellsville,  folio 
(No.  94),  1903. 

CARLL,  J.  F.:  Oil-well  Records  and  Levels.  Pennsylvania  Second  Geol. 
Survey,  vol.  II,  1877. 

BOWNOCKER,  J.  A. :  Petroleum  in  Ohio  and  Indiana.  Geol.  Soc.  America 
Bull.,  vol.  28,  p.  672,  1917. 

BOWNOCKER,  J.  A.:  Op.  tit.,  p.  673. 


232  GEOLOGY  OF  PETROLEUM 

CARLL,  J.  F.:  Geology  of  the  Oil  Regions  of  Warren, Venango,  Clarion,  and 
Butler  Counties,  Pennsylvania.  Pennsylvania  Second  Geol.  Survey,  vol. 
Ill,  1880. 

CLAPP,  F.  G. :  U.  S.  Geol.  Survey  Geol.  Atlas,  Amity  folio  (No.  144),  1907. 

U.  S.  Geol.  Survey  Geol.  Atlas,  Rogersville  folio  (No.  146),  1907. 

Economic  Geology  of  the  Amity  Quadrangle,  Eastern  Washing- 
ton County,  Pennsylvania.     U.  S.  Geol.  Survey  Bull.  300,  pp.  1-145, 1907. 

The   Nineveh   and   Gordon    Oil    Sands  in   Western  Greene 

County,  Pennsylvania.     U.  S.  Geol.  Survey  Bull  285,  pp.  262-266, 1906. 

CONDIT,  D.  D. :  Oil  and  Gas  in  the  Northern  Part  of  the  Cadiz  Quadrangle, 
Ohio.  U.  S.  Geol.  Survey  Bull.  541,  pp.  9-17, 1914. 

Structure  of  the  Berea  Oil  Sand  in  the  Summerfield  Quadrangle, 

Ohio.     U.  S.  Geol.  Survey  Bull.  621,  pp.  217-231,  1916. 

Structure  of  the  Berea  Oil  Sand  in  the  Woodsfield  Quadrangle, 

Ohio.     U.  S.  Geol.  Survey  Bull.  621,  pp.  233-249, 1916. 

FULLER,  M.  L. :  Appalachian  Oil  Fields.  Geol.  Soc.  America  Bull,  vol.  28, 
pp.  617-654,  1917. 

U.  S.  Geol.  Survey  Geol.  Atlas,  Gaines  folio  (No.  92),  1903. 

The  Hyner  Gas  Pool,  Clinton  County,  Pennsylvania.     U.  S. 

Geol.  Survey  Bull.  225,  pp.  392-395, 1903. 

GRIMSLEY,  G.  P. :  Petroleum  and  Natural  Gas  in  the  Panhandle  Counties  of 
West  Virginia.  West  Virginia  Geol.  Survey  County  Repts.,  Ohio,  Brooke,  and 
Hancock  Counties,  pp.  238-274,  1906. 

Petroleum  and  Natural  Gas  in  Pleasants,  Wood,  and  Ritchie 

Counties     West  Virginia  Geol.  Survey  County  Repts.,  Pleasants,  Wood,  and 
Ritchie  Counties,  pp.  81-204,  1910. 

GRISWOLD,  W.  T.,  and  MUNN,  M.  J.:  Geology  of  the  Oil  and  Gas  Fields  in 
the  Steubenville,  Burgettstown,  and  Claysville  Quadrangles,  Ohio,  West  Vir- 
ginia and  Pennsylvania.  U.  S.  Geol.  Survey  Bull.  318,  pp.  1-196, 1907. 

HOEING,  J.  B. :  The  Oil  and  Gas  Sands  of  Kentucky.  Kentucky  Geol.  Sur- 
vey Bull.  1,  1904. 

HUBBARD,  G.  D. :  Gas  and  Oil  Wells  Near  Oberlin,  Ohio.  Econ.  Geology, 
vol.  8,  pp.  681-690,  1913. 

MATSON,  G.  C.:  Water  Resources  of  the  Blue  Grass  Region,  Kentucky. 
U.  S.  Geol.  Survey  Water-Supply  Paper  233,  pp.  1-233,  1909. 

MILLS,  R.  V.  A.,  and  WELLS,  R.  C.:  The  Evaporation  and  Circulation  of 
Waters  Associated  with  Petroleum  and  Natural  Gas.  U.  S.  Geol.  Survey 
Bull.  693,  pp.  1-104,  1919. 

MUNN,  M.  J:  U.  S.  Geol.  Survey  Geol.  Atlas,  Sewickley  folio  (No.  176),  1911. 

U.  S.  Geol.  Survey  Geol.  Atlas,  Claysville  folio  (No.  180),  1912. 

Preliminary  Report  on  the  Oil  and  Gas  Developments  in  Tennes- 
see.    Tennessee  Geol.  Survey  Bull.  2-E,  1911. 

Oil  and  Gas  Fields  of  the  Carnegie  Quadrangle,  Pennsylvania. 

U.  S.  Geol.  Survey  Bull.  456,  pp.  1-99,  1911. 

Reconnaissance  of  the   Oil  and  Gas  Fields   in  Wayne   and 

McCreary   Counties,   Kentucky        U.   S.   Geol.   Survey  Bull.   579,   pp.   1- 
105,  1914. 


APPALACHIAN,  LIMA-IND.,  AND  MICH.  FIELDS  233 

NEWLAND,  D.  H  :  The  Mining  and  Quarry  Industry  of  New  York  State, 
1904.  New  York  State  Mus.  Buil.  93,  p.  943,  1905. 

ORTON,  EDWARD:  Petroleum  and  Natural  Gas  in  New  York.  New  York 
State  Mus.  Bull.  30,  1899. 

PANTITY,  L.  S. :  Lithology  of  the  Berea  Sand  in  Southeastern  Ohio,  and  Its 
Effect  on  Production.  Am.  Inst.  Min.  Eng.  Bull.  140,  pp.  1317-1320,  1918. 

The  Southern  Extremity  of  the  Clinton  Gas  Pools  in  Ohio.     Am. 

Inst.  Min.  Eng.  Bull,  June,  1917,  pp.  963-966. 

REEVES,  FRANK:  The  Absence  of  Water  in  Certain  Sandstones  of  the 
Appalachian  Oil  Fields.  Econ.  Geology,  vol.  12,  pp.  354-375,  1917. 

RICHARDSON,  G.  B.:  U.  S.  Geol.  Survey  Geol.  Atlas,  Indiana  folio  (No.  102), 
1904. 

SHAW,  E.  W.,  and  MUNN,  M.  J. :  U.  S.  Geol.  Survey  Geol.  Atlas,  Burgetts- 
town-Carnegie  folio  (No.  177),  1911. 

SHAW,  E.  W.,  LINES,  E.  F.,  and  MUNN,  M.  J.:  U.  S.  Geol.  Survey  Geol. 
Atlas,  Foxburg-Clarion  folio  (No.  178),  1911. 

STONE,  R.  W.:  U.  S.  Geol.  Survey  Geol.  Atlas,  Waynesburg  folio  (No.  121), 
1905. 

U.  S.  Geol.  Survey  Geol.  Atlas,  Elders  Ridge  folio  (No.  123),  1905. 

Oil  and  Gas  Fields  in  Eastern  Greene  County,  Pennsylvania. 

U.  S.  Geol.  Survey  Bull.  275,  pp.  396-412,  1904. 

•  and  CLAPP,  F.  G. :  Oil  and  Gas  Fields  of  Greene  County,  Penn- 
sylvania. U.  S.  Geol.  Survey  Bull.  304,  pp.  1-110, 1907. 

VAN  HORN,  F.  R. :  Reservoir  Gas  and  Oil  in  the  Vicinity  of  Cleveland,  Ohio. 
Am.  Inst.  Min.  Eng.  Trans  ,  vol.  56,  pp.  831-842, 1917. 

WHITE,  I.  C. :  Petroleum  and  Natural  Gas.  West  Virginia  Geol.  Survey, 
vol.  la,  1904. 

The  Mannington  Oil  Field.     Geol.  Soc.  America  Bull.,  vol.  3, 

pp.  187-216,  1892. 

and  others:  West  Virginia  Geol.  Survey  County  Repts. 

WOOLSEY,  L.  H  :  Economic  Geology  of  the  Beaver  Quadrangle,  Pennsyl- 
vania.    U.  S.  Geol.  Survey  Bull.  286,  pp.  1-132,  1906. 

Kentucky. — The  rocks  exposed  in  Kentucky1  are  Paleozoic, 
Cretaceous,  and  Quaternary.  (See  Figs.  102,  103.)  The  most 
prominent  structural  feature  of  this  State  is  the  Cincinnati  anti- 
cline, which  in  Ohio  and  Indiana  is  termed  the  Cincinnati  arch. 
(Seep.  201.)  This  anticline  extends  southward  from  Cincinnati/ 
through  east-central  Kentucky  and  passes  out  of  the  State  in  the! 
eastern  part  of  Monroe  County.  In  Tennessee  it  expands  into  a 
great  dome  in  the  region  of  Nashville.  From  Tennessee  it  passes 
southward  into  Alabama. 

BOEING,  J.  B. :  Oil  and  Gas  Sands  of  Kentucky.  Kentucky  Geol.  Survey 
Bull  1,  1904. 

FOHS,  F.  J. :  Oil  and  Gas  Possibilities  of  Kentucky.  Am.  Inst.  Min.  Eng. 
Bull.  99,  pp.  621-628,  1915. 


GEOLOGY  OF  PETROLEUM 


APPALACHIAN,  LIMA-IND.,  AND  MICH.  FIELDS  235 


A  zone  of  deformation  known  in 
anticline  extends  into  Kentucky, 
where  it  is  known  as  the  Camp- 
ton  anticline.  (See  Fig.  90.)  This 
anticline  crosses  Kentucky  from 
east  to  west  and  intersects  the 
Cincinnati  arch  near  the  north 
border  of  Lincoln  County. 

The  oldest  formation  in  the 
State,  the  Mohawkian  (Ordo- 
vician),  is  exposed  at  the  crest  of 
this  arch  in  Jessamine  County. 
This  portion  has  been  termed  the 
Jessamine  dome.  Around  the 
Mohawkian  is  a  great  area  of. 
Cincinnatian  rocks  (Ordovician). 
Silurian,  Devonian,  Mississip- 
pian,  and  Pennsylvanian  rocks 
occur  in  succession  stratigraphi- 
cally  above  the  Ordovician  cen- 
tral mass.  The  dip  of  the  beds  is 
essentially  eastward  to  the  West 
Virginia  border;  the  Pennsyl- 
vanian coal  measures  in  eastern 
Kentucky  lie  on  the  west  limb  of 
the  great  Appalachian  coal  basin. 
In  the  coal  region  the  rocks  are 
thrown  into  gentle  folds  like  those 
in  West  Virginia.  West  of  the 
Cincinnati  anticline  the  beds 
dip  westward  below  the  western 
coal  basin  and  rise  again  near  the 
Cumberland  River. 

Most  of  the  oil  and  gas  pro- 
duced in  Kentucky1  is  derived 
from  Devonian  limestone,  but 
some  is  obtained  also  from  Ordo- 


West  Virginia  as  the  Warfield 


W.  R. :  The  Oil  and  Gas 
Resources  of  Kentucky.  Kentucky 
Dept.  Geology  and  Forestry,  ser.  5,  vol.  1,  pp.  1-630, 1919. 


GEOLOGY  OF  PETROLEUM 


APPALACHIAN,  LIMA-IND.,  AND  MICH.  FIELDS  237 


Field 

County 

System 

Formation 

.Structure 

1    Clover  Port  (0) 

Breckinridge 
Meade. 
Ohio. 
Grayson. 
Do. 
Edmonson. 
Logan. 
Allen. 
Do. 
Do. 
Do. 
Allen 
Allen. 
Allen. 
Barren. 
Barren. 
Barren. 
Barren. 
Wayne. 

Lincoln. 

Knox. 
Clay 
Owsley. 
Breathitt. 
Estill. 
Estill. 
Estill. 
Lee. 
Powell. 
Wolfe. 
Do. 
Morgan. 
Menefee   and 
Powell. 
Bath. 
Bath     and 
others. 
Lawrence. 
Do. 
Do. 
Johnson    and 
Lawrence. 
Johnson    and 
Morgan. 
Magoffin. 
Knott. 

Knott. 
Martin. 
Warren. 
Do. 
Cumberland. 

M 

D 
D? 
M 
M 

D 
S,  D 
D 
S,  D 

S 
S 
S,  D 
D 
M 
S 
S,  D 
0,  S,  M 

D 

P 
M 
D,  M 
D 
D 
D 
S,  D 
S,  D 
D 
D 
D 
D 

D 
D 

D 
M 
M 
M 

M 

M 
M 
M,  P 

D,  M,  P 
M 
D 
S,  D 
0 

Warsaw. 
Sand. 
Do. 
Waverly. 
Do. 

Dome. 

(?) 
Anticline. 
(?) 
(?) 
Dome. 
Monocline. 
Anticline. 
Do. 
Do. 

Anticline. 

(?) 
(?) 
Anticlines  ard 
synclines. 
Anticline. 

Anticline. 
Anticline. 
Anticline. 
Anticline. 
Anticline. 
Anticline. 
Anticline. 
Anticline. 
Do. 
Do. 
Do. 

Monocline. 

(?) 

Monocline. 
Syncline. 
Monocline. 
Do. 

Dome. 

Dome. 
Dome. 
Syncline. 

Anticline. 
(?) 

(?) 
(?) 

2    Rock  Haven  (g)        

3.  Hartford  (o)  
4    Caneyville  (o)                    .  . 

5    Leitchfield  (o) 

6    Bear  Creek  (g) 

7.  Diamond  Springs  (0)  
8    Jewell  (o) 

Waverly,  Cypress. 
Onondaga. 
Niagara,  Onondaga  . 
Onondaga. 
Niagara,  Onondaga. 
Niagaia. 
Do. 
Niagara,  Onondaga  . 
Onondaga. 
Warsaw. 
Niagara. 
Niagara,  Onondaga  . 
Many  sands. 

Onondaga. 

Several. 
Big  Injun. 
(?) 
Onondaga. 
Onondaga. 
Onondaga. 
Niagara,  Onondaga. 
Niagara,  Onondaga. 
Onondaga. 
Do. 
Do. 
Do. 

Do. 
Do. 

Do. 
Berea. 
Do. 
Berea,  Wier. 

Do. 

Wier. 
Pottsville,  Wier. 
Mauch     Chunk, 
Pottsville. 
Several. 
Big  lime,  Big  Injun. 
Onondaga. 
Niagara,  Onondaga  . 
TVenton? 

9    Gainsville  (o)  

10    Butlersville  (o)  

11    Halfway  (o)    

12.  Rodemer  and  Petroleum  (o) 
13    Adolphus  (o)  

14   Scottsville  (o)  

15    Steffy  (o)          

16    Oil  City  (o)    

17    Hiseville  (g)    

18.  Oskamp  (o)  
19.  Wayne  County  (o)  

20.  Buck  Creek  (o)  
21.  Little  Richland  (Barbour- 
ville)  (o)  
22.  Burning  Springs  (g)  
23.  Island  Creek  (o)  
24.  Frozen  Creek  (o)  
25.  Ross  Creek  (o)  
26.  Station  Camp  (o)  
27    Irvine  (o)                

28.  Big  Sinking  (o)  
29.  Ashley  (o)  
30    Campton  (o) 

31    Still  water  (o) 

32.  Cannel  City  (o)  
33    Menefee  (g) 

34    Olympia  (o) 

35    Ragland  (o)            

36    Fallsburg  (o) 

37.  Busseyville  (o)  
38.  Georges  Creek  (o)  
39.  Laurel  Creek  (o)  

40.  Point  Creek  (o)  

42.  Beaver  Creek  (o)  

43.  Beaver  Creek  (g)  
44.  Inez  (g)  

45    Moulder  (o) 

46.  Green  Hill  (o)  

47.  Burksville  (o)  

238  GEOLOGY  OF  PETROLEUM 

vician,  Silurian,  Mississippian,  and  Pennsylvanian  rocks.  Any 
porous  limestone,  where  covered  with  shales,  may  serve  as  a  reser- 
voir. The  reservoir  limestones  are  not  uniformly  porous,  and  the 
production  is  therefore  spotted. 

Both  east  and  west  of  the  Cincinnati  arch,  at  places  not  far  from 
the  coal  measures,  are  areas  of  bituminous  sandstones.  These 
are  shown  on  a  map  by  Eldridge. l  They  appear  not  to  be  closely 
connected  with  the  oil  pools. 

GENERAL  SECTION  FOR  KENTUCKY  FIELDS 
(Based  on  Sections  by  Hoeing,  Matson  and  Jillson) 

Pennsylvanian : 

Pottsville  conglomerate;  alternating  sands,  shales,  and  coals,          Feet 
conglomerate  at  base;  contains  Beaver,  Horton,  and  Pike 
sands  in  Floyd,  Knott,  and  Pike  Counties,  and  Wages,  Jones, 
and  Epperson  sands  in  Knox  County 60-1,000 

Mississippian: 

Chester  and  Mauch  Chunk  shales  and  sandstone,  some  lime- 
stone; contains  Maxon  sand.  In  eastern  Kentucky  30  to  275 
feet  thick;  in  western  Kentucky 300-  800 

St.  Genevieve;  fine  sands,  oolitic  white  limestone  (Big  lime). 

Thickness  in  eastern  Kentucky 20-  400 

St.  Louis;  fine  gray-white  limestone.  Thickness  in  western 

Kentucky 475-1,000 

Waverly  sandstones  and  shales.  In  eastern  Kentucky  400  to 
GOO  feet  thick;  contains  Keener,  Big  Injun,  Squaw,  Wier,  and 
Berea  sands.  In  western  Kentucky  calcareous  shales  and 
limestone;  contains  amber  oil  of  Barren,  Warren  and  Simpson 
Counties.  Thickness  in  western  Kentucky 400 

Devonian  system:2 

Ohio  shale;  in  shallow  wells  yields  an  abundance  of  highly  min- 
eralized water 150 

"Corniferous  limestone,"  usually  a  cherty  magnesian  lime- 
stone with  some  shale  beds.  Oil  sand  in  Irving  region 30 

Silurian  system: 

Niagaran;  blue  shales  and  yellow  limestones,  in  places  contain- 
ing chert;  locally  includes  some  sandstone.  Oil  in  Allen 

County 60 

IELDRIDGE  G.  H. :  Asphalt  and  Bituminous  Rock  Deposits  of  the  United 
States.  U  S.  Geol.  Survey  Twenty-second  Ann.  Repi.  part  1,  pi.  26,  opp.  p. 
240,  1901. 

2The  section  of  the  Devonian  and  older  rocks  represents  the  central  Blue  Grass  region,  after 
MATSON,  G.  Cr  U.  S,  Geol,  Survey  Water-Supply  Paper  233,  1909. 


APPALACHIAN,  LIMA-IND.,  AND  MICH.  FIELDS  239 

Ordovician  system: 
Richmond  formation: 

Upper  division,  heavy-bedded  gray  or  blue  arenaceous  lime- 
stones, with  about  10  feet  of  dense  calcareous  shale  in 

lower  part;  locally  an  impure  sandstone 60 

Middle  division,  blue  shale,  with  some  blue  or  dove-colored 

limestone 125 

Lower  division,  interbedded  blue  limestone  and  shale 80 

Maysville  formation;  interbedded  blue  limestones  and  shales, 
the  alternate  layers  usually  thin  and  nodular;  most  of  the 

beds  thin 230 

Eden  shale;  mainly  bluish  shale,  but  upper  part  is  commonly 

sandy  (Garrard  sandstone) 200  + 

Winchester  limestone;  generally  yields  moderate  amounts  of 

strong  brines 60+ 

Lexington  limestone: 

Upper  division,  gray,  crystalline  and  cherty  (Flanagan  chert) ; 

commonly  yields  much  salt  or  saline-sulphur  water 75 

Middle  division,  light-drab  argillaceous  limestone,  with  shale 
beds;  uppermost  part,  20  to  60  feet  thick,  is  commonly 
sandstone,  with  some  phosphatic  limestone;  yields  some 

strongly  mineralized  water 194 

Lower  division,  heavy  bedded,  coarse  grained,  crystalline, 

and  cherty 30 

Highbridge  limestone;  mainly  limestone,  with  shale  lenses; 
little  sandstone;  yields  moderate  amounts  of  salt  and  salt- 
sulphur  water,  especially  from  beds  near  the  top 400 

Unidentified  limestone,  similar  to  Highbridge  limestone 100 

St.  Peter  "sandstone;"  a  siliceous  limestone,  yielding  large  quan- 
tities of  salt-sulphur  water.  Thickness  unknown. 

Most  of  the  gas  fields  are  in  the  northeastern  part  of  the  State, 
although  there  are  a  few  along  the  Ohio  River  in  northwestern 

i.  Kentucky.1    The  location  of  oil  and  gas  pools  is  shown  on  Fig.  104 

i  after  Jillson. 

The  Campton  oil  pool  is  in  Wolfe  County,  about  50  miles  south- 
east of  Lexington.  The  field  as  it  was  developed  in  1909  is  roughly 

f  crescent-shaped,  with  a  length  of  about  3^  miles  and  a  maximum 
width  of  1^2  miles.2    The  rocks  that  crop  out  in  the  Campton 

:  field  are  of  Pennsylvanian  age,  belonging  to  the  lower  part  of  the 
Pottsville  group.     The  oil  probably  occurs  in  a  sand  layer  of  the 

^LAPP,  F.  G. :  Natural  Gas  in  the  United  States.  Econ.  Geology,  vol.  8, 
p.  522,  1913. 

2MuNN,  M.  J.:  The  Campton  Oil  Pool,  Kentucky.  U.  S.  Geol.  Survey 
Bull.  471,  p.  9,  1912. 


240  GEOLOGY  OF  PETROLEUM 

Devonian,  which  Munn  considers  as  the  Corniferous.  The  Camp- 
ton  sand  has  two  pay  streaks  in  which  oil  occurs  in  the  northeastern 
part  of  the  field.  These  are  as  a  rule  from  24  to  28  feet  apart,  and 
each  probably  ranges  from  3  to  10  feet  in  thickness.  In  the  central 
and  southern  parts  of  the  field  rarely  more  than  one  pay  streak  is 
found.  This  is  from  1  foot  to  about  14  feet  below  the  top  of  the 
sand.  The  field  lies  on  a  monocline,  on  which  is  developed  a 
plunging  anticline.  The  south  half  of  the  field  lies  along  the  axis 
and  sides  of  a  broad,  low  secondary  fold.  Over  part  of  the  terri- 
tory the  contour  on  the  oil  sand  220  feet  below  sea  level  marks 
the  dividing  line  below  oil  and  salt  water.  As  stated  by  Munn,  salt 
wells  form  almost  a  semicircle  around  the  south  half  of  the  district. 

The  Menifee  gas  field1  is  in  Menifee  County,  about  20  miles 
northeast  of  the  Campton  pool.  The  rocks  are  of  Pennsylvanian, 
Mississippian,  and  Devonian  age.  The  Devonian  rocks,  however, 
do  not  crop  out.  The  gas  is  found  in  the  Onondaga  or  Corniferous 
(Devonian)  limestone  just  below  the  Ohio  shale.  On  June  1,  1912, 
the  production  was  reported  to  be  approximately  25,000,000  cubic 
feet,  and  the  gas  had  a  closed  pressure  of  about  60  pounds  to  the 
square  inch.  The  Corniferous  limestone  is  gas-bearing  on  a  mono- 
cline between  the  290-foot  contour  on  the  south  side  of  the  field 
and  the  500-foot  contour  on  the  north  side,  the  maximum  differ- 
ence in  the  height  of  the  top  of  this  bed  in  the  field  being  more 
than  200  feet. 

The  Ragland  oil  field  is  about  15  miles  northeast  of  the  Menifee 
gas  field.  The  surface  rock  is  of  Mississippian  age,  the  beds  being 
essentially  the  same  as  in  the  Menifee  field.  The  Corniferous2 
limestone  carries  the  oil.  This  formation  varies  greatly  in  thick- 
ness. At  some  places  it  is  absent;  at  Campton  it  is  probably  200 
feet  thick;  at  Irvine,  a  pool  some  20  miles  southwest  of  Menifee,  it 
is  only  20  feet  thick.  The  oil  and  gas  bearing  portion,  or  "pay 
streak,"  as  it  is  called,  varies  greatly  in  position  and  thickness  from 
well  to  well.  Its  porosity  is  due  to  numerous  minute  cavities, 
many  of  which  are  of  microscopic  size. 

The  Irvine  oil  field3  is  on  the  western  edge  of  the  Appalachian 

JMuNN,  M.  J. :  The  Menifee  Gas  Field  and  the  Ragland  Oil  Field,  Ken- 
tucky. IT.  S.  Geol.  Survey  Bull.  531,  p.  9,  1913. 

2In  this  region  the  "Corniferous"  is  the  Onondaga. 

=»SHAW,  E.  W. :  The  Irvine  Oil  Field,  Estill  County,  Kentucky.  U.  S.  Geol. 
Survey  Bull.  661,  pp.  149-150,  1918. 


APPALACHIAN,  LIMA-IND.,  AND  MICH.  FIELDS  241 

coal  basin,  a  few  miles  east  of  the  eastern  border  of  the  broad  area 
of  Ordovician  limestones.  A  southeastward  dip  carries  the  Ordo- 
vician  beneath  successively  younger  rocks  of  Silurian  and  Devon- 
ian age,  which  crop  out  immediately  west  of  Irvine.  To  the  east 
these  rocks  are  overlain  by  rocks  of  Carboniferous  age  (Missis- 
sippian  and  Pennsylvanian). 


FIG.  105. — Cross-section  from  Irving  to  Campton,  Kentucky,  showing  the 
dip  and  thickening  of  formations  to  the  east,  the  structural  features  on  which 
oil  and  gas  are  found  and  the  general  attitude  of  the  surface.  (After  Shaw.) 

As  a  general  rule  the  formations  thicken  toward  the  east.  The 
top  of  the  Mississippian  series  in  the  western  part  of  the  Irvine 
field  averages  about  640  feet  above  the  oil  sand  or  "Corniferous" 
limestone,  whereas  in  the  eastern  part  of  the  field  it  is  about  700 
feet  above;  in  the  Campton  field,  20  miles  to  the  east,  it  is  about 
850  feet;  and  in  the  east  end  of  Wolfe  County  nearly  1,000  feet. 
This  gradual  eastward  divergence  of  the  Maxville  (?)  and  Cornif- 
erous limestones  is  illustrated  in  Fig  105. 


FIG.  106. — Profile  of  the  oil  sand  across  the  Irvine  field,  Kentucky.   (After 
Shaw,  U.  S.  Geol.  Survey.) 

A  fault  zone  borders  the  crest  of  the  Irvine  anticline  on  the 
northwest.  The  effect  of  the  faulting  is  to  drop  a  block  of  strata 
from  half  a  mile  to  2  miles  wide  and  probably  more  than  20  miles 
long,  25  to  200  feet  (Fig.  106). 

The  Irvine  fault  zone  is  nearly  parallel  to  the  axis  of  the  Irvine 
anticline.  It  runs  northeastward  from  Irvine,  curves  gradually 
to  an  east  or  slightly  north  of  east  course  from  Estill  Furnace  to 
High  Rock,  bends  slightly  south  of  east,  and  at  Glen  Cairn  resumes 
an  eastward  course. 


242 


GEOLOGY  OF  PETROLEUM 


COMBINED  SECTION  IN  ESTILL  COUNTY,  KENTUCKY 

(After  Shaw.  The  column  showing  depth  has  been  recalculated  to  conform  with 

other  sections) 


Thick- 
ness 

Depth 

Geologic  Formation 

Heavy  sandstone 

Feet 

196 

Feet 
196 

Shales  and  shaly  sandstone  
Black  slate    

50 
4 

246 
250 

Coal  

1 

251 

Conglomerate 

Gray  shales  .         .                .... 

4 

255 

measures. 

Coal  

1 

256 

Shales                    .         

15 

271 

Buff  earthy  limestones  

8 

279 

Archimedes  limestone  

2 

281 

[Chester,  33  feet. 

Gray  limestone 

13 

294 

Calcareous  shales  

10 

304 

Oolitic  limestone 

10 

314 

Buff  limestone       

11 

325 

Semioolitic  limestone 

22 

347 

Gray  limestones  

12 

359 

Earthy  buff  limestone 

5 

364 

[St.  Louis,  150  feet. 

Thin  gray  cherty  limestones  
Massive  limestone 

24 
22 

388 
410 

Blue  limestone  and  shale  

38 

448 

Earthy  yellow  limestone 

6 

454 

Sandstones  and  shales  

490 

944 

Waverly,  490  feet. 

Black  shale 

125 

1,069 

Devonian  shales,  125ft. 

Estill  County  oil  sand  

25 

1,094 

Corniferous,  25  feet. 

Blue  and  gray  shales. 

145 

1,239 

}  Niagara,  150  feet. 

Gray  lime     

5 

1,244 

Gray  lime              • 

25 

1,269 

| 

Gray  shale     

10 

1,279 

>Cilnton,  53  feet. 

Gray  lime 

8 

1,287 

Red  lime  

10 

1,297 

Gray  lime                 .... 

17 

1,314 

Brown  lime  

40 

1,354 

Gray  lime 

839 

2,193 

Greenish-white  friable  shaly  sand- 
stone   

10 

2,203 

Lower  Silurian  (Ordo- 

Hard  fine-grained  limestone,  dark 
dove  -  color,     with     occasiona 
bands  of  dark-blue  hard  lime 
stone              

425 

2,628 

vician),        Hudson 
and   Trenton 
groups,  1,476  feet. 

Hard  gray  limestone       .        .... 

145 

2,773 

White  fine-grained  sand  and  lime 
Bottom  of  Whiteoak  well. 

15 

2,788 

Calciferous(St.Peter?). 

APPALACHIAN,  LIMA-IND.,  AND  MICH.  FIELDS  243 

The  "pay"  or  oil-bearing  portion  of  the  oil  "sand,"  differs  from 
the  remainder  of  the  limestone  or  dolomite  in  having  larger  pores 
and  in  being  softer  or  less  indurated.  In  places  it  is  cavernous. 
As  this  character  is  due  to  recrystallization,  it  is  extremely  irregular 
in  development.  After  penetrating  the  soft,  more  or  less  sticky 
clay  shale  that  overlies  the  oil  sand  the  drill  commonly  enters  a 
rather  hard  limestone  or  cap  rock,  which  here  and  there  yields 
water  and  which  ranges  from  a  few  inches  to  several  feet  in  thick- 
ness. Below  this  rock  is  the  soft  brown  sandy-textured  magnesian 
limestone  that  constitutes  the  oil  reservoir.  In  the  eastern  part 
of  the  field,  where  the  whole  "sand"  is  thicker,  oil-bearing  strata 
are  found  at  more  than  one  horizon. 

Most  of  the  wells  in  the  Irvine  field  yield  little  gas.  Salt  water 
is  probably  present  in  the  lower  part  of  the  oil  sand  throughout 
much  of  the  field,  particularly  the  southern  half,  and  many  wells 
bordering  the  field  have  yielded  considerable  quantities  of  water. 
Along  the  northern  border,  however,  wells  that  fail  to  produce  oil 
are  commonly  reported  altogether  dry. l 

Oil  was  first  discovered  in  quantity  in  Knox  County  in  1840, 
when  a  well  drilled  for  brine  on  Little  Richland  Creek,  about  6 
miles  north-northeast  of  Barbourville,  began  flowing  oil  at  a  rate  of 
probably  100  barrels  a  day  from  a  shallow  depth.  All  the  out- 
cropping rocks  of  Knox  County  belong  to  the  Pottsville  group. 
They  consist  chiefly  of  sandstone  and  shale  but  also  include  several 
beds  of  coal,  clay,  and  probably  limestone.  The  sands  that  have 
furnished  oil  and  gas  in  paying  quantities  in  Knox  County,  named 
in  ascending  order,  are  the  Epperson  sand,  the  Lower  and  Upper 
Jones  sands,  and  the  Lower  and  Upper  Wages  sands  of  Pottsville 
age.  They  are  all  white  or  gray  sandstones,  containing  soft  porous 
pay  streaks  in  which  oil  and  gas  are  found.  The  structure2  is  said 
to  be  monoclinal,  with  small  terraces  locally  developed.  About 
50  holes  were  drilled  in  Knox  County  in  1917,  and  some  of  them 
proved  to  be  50-barrel  wells.3 

In  the  Wayne  County  and  McCreary  County  fields,  in  southern 

JSHAW,  E.  W. :  Op.  cit.,  p.  176. 

2MuNN,  M.  J.:  The  Campion  Oil  Pool,  Kentucky.  U.  S.  Geol.  Survey 
Bull  471,  p.  19,  1912. 

'PEMBERTON,  J.  R.  i  A  Resum6  of  the  Past  Year's  Development  in  Ken- 
tucky from  a  Geological  Standpoint.  Am.  Assoc.  Pet.  Geologists  Bull  2, 
pp.  38-53,  1918. 


244  GEOLOGY  OF  PETROLEUM 

Kentucky,  the  oil  is  in  Ordovician,  Silurian,  and  lower  Mississip- 
pian  rocks.  At  some  places  no  salt  water  is  present  and  the  oil 
lies  in  synclines. 

At  Busseyville,  in  Lawrence  County,  northeastern  Kentucky, 
the  oil  is  in  a  monocline  and  comes  from  Pottsville,  Mississippian, 
and  Devonian  rocks  at  depths  between  700  and  2,000  feet. 

At  Petroleum,  in  Allen  County,  oil  is  found  in  anticlines  and 
synclines,  in  Silurian  rocks,  at  depths  of  80  to  300  feet. 

In  the  Hartford  field,  Ohio  County,  western  Kentucky,  the  oil 
is  found  probably  in  the  Devonian,  in  a  broad  anticline,  at  depths 
of  1,500  to  1,700  feet. 

Tennessee. — Tennessee  is  divided  into  three  geologic  provinces 
(Fig.  107).  In  the  eastern  part  of  the  State  there  is  a  broad  belt  of 
closely  folded  rocks  ranging  from  Cambrian  or  older  to  Carbonifer- 
ous. These  rocks  are  extensively  faulted  and  so  far  as  known 
contain  no  oil  or  gas.  The  western  part  of  the  State  is  occupied 
by  Cretaceous,  Tertiary,  and  Quaternary  rocks,  which  are  appar- 
ently flat  or  dip  at  low  angles.  The  central  part  of  the  State  is 
lower  in  elevation  than  the  eastern  and  western  parts  and  is  known 
as  the  central  basin.  The  oldest  rocks  in  this  basin  are  of  Ordo- 
vician age  and  consist  of  limestones  and  calcareous  shales.  Sur- 
rounding the  Ordovician  is  a  great  belt  of  Devonian  and  Missis- 
sippian rocks.  East  of  the  Mississippian  is  a  broad  belt  of  Penn- 
sylvanian  conglomerate,  sandstones,  shales,  and  beds  of  coal.  The 
Pennsylvanian  belt  is  only  about  35  to  50  miles  wide,  and  at  some 
places  the  coal  beds  are  eroded. 

Although  oil  seeps  of  considerable  size  have  been  known  in 
Tennessee  for  many  years, 1  the  production  is  small.  In  the  Spring 
Creek  district,  about  80  miles  east  of  Nashville,  oil  in  small  quan- 
tities is  produced  from  wells  in  the  Fort  Payne  formation  (Missis- 
sippian) at  depths  less  than  30  feet.  In  the  Superior  and  River- 
ton  districts,  northeast  of  the  Spring  Creek  district,  the  lowest 
outcropping  formation  is  the  Fort  Payne  of  Mississippian  age, 
consisting  of  calcareous  shale,  a  thin  sandstone,  some  limestone, 
and  bedded  chert.  Underlying  the  Fort  Payne  formation  and 
entirely  below  drainage  level  is  the  Chattanooga  shale  (Devonian), 
ranging  from  25  to  30  feet  in  thickness.  The  oil  and  gas  are  ir 
the  Ordovician  rocks  below  the  Chattanooga  shale,  and  are  fourd 

JMuNN,  M.  J. :  Preliminary  Report  on  the  Oil  and  Gas  Developments  in 
Tennessee,  Tennessee  Geol.  Survey  Bull  2-E,  pp.  9-10,  1911. 


APPALACHIAN,  LIMA-IND.,  AND  MICH.  FIELDS  245 


t 

4 

ft. 

e 


246 


GEOLOGY  OF  PETROLEUM 


at  numerous  horizons  through  more  than  1,500  feet  of  strata, 
though  most  of  the  production  comes  from  the  upper  500  feet. 
Most  of  the  oil  is  a  heavy  dark-green  to  black  oil,  but  in  a  number 
of  wells  a  light  amber-colored  oil  of  excellent  quality  has  been 
found.  A  little  salt  water  is  present. 

RECORD  OF  LACEY  No.  1  WELL,  SPURRIER,  TENNESSEE 


Thickness 

Depth 

Shales    6tc                                               

Feet 
64 

Feet 
64 

Chattanooca  shale                                   

28 

92 

Limestone  and  shale                 

268 

360 

Limestone  siliceous  (brown)             

373 

733 

Shale  blue  soft                 

150 

883 

Limestone  and  shale  alternating  

117 

1,000 

In  1916  a  well  was  drilled  on  the  creek  flats  about  three-quarters 
of  a  mile  northwest  of  Glenmary,  Scott  County.1  Oil  was  en- 
countered in  a  stratum  in  the  St.  Louis  formation  at  a  depth  of 
1,232  feet.  The  production  was  10  to  20  barrels  a  day.  The 
stratum  is  8  feet  thick  and  is  reported  by  drillers  to  be  a  sand,  but 
according  to  Glenn  it  is  probably  an  oolitic  limestone.  The  oil  is 
dark  green  and  of  good  grade.  There  was  little  gas  with  the  oil. 
The  rocks  at  Glenmary  are  part  of  a  long  monocline  that  rises 
gently  to  the  west  or  west-northwest.  The  rate  of  rise  at  Glen- 
mary is  between  30  and  40  feet  to  the  mile.  No  evidence  was 
found  of  any  fold  or  flattening  or  other  interruption  of  this  general 
monocline. 

There  are  numerous  anticlines  in  western  Tennessee  in  the  Pale- 
ozoic rocks,  but  folds  that  inclose  permeable  rocks  overlain  by 
shales  seem  to  be  rare.  Oil  has  also  been  reported  to  occur  in 
the  Eocene  rocks  at  the  west  end  of  the  State,  but  the  report  is 
unconfirmed.  These  rocks  are  similar  in  general  character  to  some 
of  the  beds  in  the  salt-dome  region  of  the  Gulf  coast. 

^LENN,  L.  C. :  Recent  Oil  Development  at  Glenmary,  Tennessee. 
Resources  of  Tennessee,  vol.  7,  p.  40,  1917. 


APPALACHIAN,  LIMA-IND.,  AND  MICH.  FIELDS  247 
RECORD  OF  PEMBERTON  WELL  No.  1,  GLENMARY,  TENNESSEE" 

Feet 

Soil 0-3 

Hard  white  sand 3-45 

Black  slate 45-150 

Hard  white  sand 150-305 

Slate 305-435 

Coarse  loam  sandstone;  salt  water  at  505  feet 435-540 

Black  slate 540-547 

Hard  white  sandstone,  base  of  Lee 547-730 

Slate  and  lime  shells,  top  of  Pennington 730-775 

Red  shale 775-795 

Black  slate 795-822 

Dark  lime 822-895 

Red  shale 895-908 

Dark  lime 908-930 

Black  slate,  base  of  Pennington 930-950 

Limestone,  top  of  St.  Louis;  a  little  show  of  gas  at  1045 

feet 950-1048 

White  slate 1048-1051 

Dark  lime 1051-1144 

Black  slate 1144-1147 

Gray  sand 1147-1155 

Hard  white  lime 1155-1232 

Gray  sand  and  small  pebble,  oil-bearing 1232-1240 

Hard  white  lime 1240-1244 

°GLENN,  L.  C.:  Op.  cit.,  p.  42. 

Alabama. — The  Fayette  gas  field1  is  about  50  miles  west  of 
Birmingham,  Alabama,  in  the  western  part  of  the  Warrior  coal 
field.  Gas  and  some  oil  were  found  in  1909  in  a  drill  hole  put  down 
for  oil.  Several  wells  dug  later  yielded  large  flows  of  gas  with  high 
pressure  at  about  1,400  feet.  With  the  exception  of  a  compar- 
atively thick  covering  of  sand,  clay,  and  gravel,  of  Cretaceous  and 
later  age,  the  rocks  penetrated  by  the  drill  in  the  Fayette  district 
appear  to  belong  entirely  to  the  Pottsville  formation,  which  con- 
sists of  shales  with  included  sandstone  beds  and  coal. 

The  general  structure  of  the  Warrior  coal  basin,  in  which  the 
Fayette  gas  field  lies,  is  that  of  a  broad,  flat  basin,  gently  tipped  to 
the  southwest.  Several  of  the  gas  wells  appear  to  tap  the  sands 
on  the  limbs  of  a  gentle  anticline.  The  data  are  not  now  sufficient 
to  show  the  general  relation  of  the  gas  sands  to  the  structure. 

!MUNN,  M.  J.:  The  Fayette  Gas  Field,  Alabama.  U.  S.  Geol.  Survey 
Bull.  471,  pp.  30-55,  1912. 


248 


GEOLOGY  OF  PETROLEUM 


LIMA-INDIANA  OR  TRENTON  FIELD 

The  Trenton  limestone  oil  and  gas  field  of  Ohio  and  Indiana 
(Fig.  108)  occupies  a  large  area  that  extends  with  interruptions 


from  Lake  Erie  to  a  point  near  Marion,  Indiana.1     The  width  of 
the  field  varies  greatly;  at  some  places  it  is  sufficient  for  only  a  few 
^OWNOCKER,  J.  A. ;  Petroleum  in  Ohio  and  Indiana.     Geol.  Soc.  America 
Bull,  vol.  28,  p.  670,  1917. 


APPALACHIAN,  LIMA-IND.,  AND  MICH.  FIELDS  249 


rows  of  wells,  but  at  others  it  is  20  miles  or  more.  It  is  said  that 
30,000  wells  have  been  drilled  in  the  Indiana  portion  of  the  Tren- 
ton field,  and  a  larger  number  in  Ohio.  The  output  from  the  field 
in  Ohio  attained  its  maximum  in  1896,  exceeding  25,250,000  bar- 
rels. The  maximum  production  in  Indiana  was  in  1904,  when  the 
yield  was  about  11,300,000  barrels.  The  pressure  and  production 
have  greatly  declined  in  recent  years.  The  Trenton  oil  is  sul- 
phurous  and  has  a  paraffin  base.  The  gas  is  about  92  per  cent 
methane. 

Surface  indications  of  oil  and  gas  are  rare  in  this  field.  Never- 
theless they  led  to  its  development.  Prospecting  was  first  carried 
on  in  the  vicinity  of  Findlay,  Ohio,  where  gas  seeps  were  common 
and  where  as  early  as  1838  gas  was  utilized  in  a  small  way  for 
domestic  heating.  Gases,  including  sulphureted  hydrogen,  filling 
cisterns  were  so  common  as  to  be  regarded  as  a  nuisance.  These 
seeps  led  to  the  development  of  the  Findlay  pool  in  1865.  {This 
pool  was  shown  by  drilling  to  be  on  a  structural  dome  having  about 
200  feet  of  closure. 

The  rock  successions  in  Ohio  and  Indiana  are  shown  by|  the 
following  well  records.1 


INDIANA 

Thi<ikness 
(Feet) 

Niagara  limestone 153 

Hudson  River  limestone 451 

Utica  shale '   300 

Trenton  limestone  at .  .  954 


OHIO 

Thickness 
(Feet) 

Niagara  limestone 167 

Niagara    shale    and    Clinton 

limestone 108 

Medina  shale 47 

Hudson  River  shale  and  lime- 
stone        462 

Utica  shale 300 

Trenton  limestone  at 1,092 


So  regular  are  the  formations  that  approximately  similar  well 
records  can  be  furnished  by  the  thousands,  though  there  is  con- 
siderable variation  in  the  depths  of  wells  due  to  their  position  with 
reference  to  folding.  In  the  Ohio  fields  the  depth  to  the  Trenton 
usually  ranges  from  1,000  to  1,500  feet,  but  in  Indiana  the  depth 
is  more  uniform  and,  according  to  Blatchley,2  averages  1,000  feet. 

iQRTON,  EDWARD:  Ohio  Geol.  Survey,  vol.  6,  p.  112,  1888. 

BLATCHLEY,  W.  S.:  Indiana  Dept.  Geology  and  Nat  Res.,  Twenty-first 
Ann.  RspL,  p.  68,  1897. 

2Op.  tit.,  p.  68. 


250 


GEOLOGY  OF  PETROLEUM 


The  principal  "pay  rock"  usually  lies  within  50  feet  of  the  top  of 
the  Trenton,  and  in  early  days,  in  the  Ohio  part  of  the  field,  it  was 
a  general  belief  among  drillers  that  unless  oil  were  found  when  the 
drill  had  penetrated  50  feet  of  the  limestone  it  was  useless  to  con- 


FIG.  109. — Map  showing  the  structure  of  the  Lima-Indiana,  or  Trenton 
limestone  oil  and  gas  field,  Ohio  and  Indiana,  by  contours  on  the  top  of  the 
Trenton  limestone.  (After  Orton.}  Sections  on  lines  AB,  etc.,  are  shown  in 
Fig.  10. 

tinue  sinking.  Later,  however,  a  second  and  a  third  "pay"  were 
found,  but  these  have  proved  of  small  value  in  comparison  with 
the  first. 

The  structure  of  the  Trenton  limestone  has  a  marked  relation  to 


APPALACHIAN,  LIMA-IND.,  AND  MICH.  FIELDS251 


Fia.  110. — Sections  through  Lima-Indiana  oil  and  gas  field  along  lines  AB,  CD, 
etc.,  Fig.  109.   (Redrawn  f^om  sections  by  Edward  Orion.) 


252  GEOLOGY  OF  PETROLEUM 

the  production  of  oil.  The  region  is  a  broad,  flat-topped  anticline 
that  has  formed  as  a  warping  on  the  Cincinnati  arch.  The  Cin- 
cinnati axis  crosses  the  Ohio  River  a  short  distance  east  of  Cin- 
cinnati. Northward  from  that  place  it  bifiurcates,  one  arm  extend- 
ing northwestward  toward  the  south  end  of  Lake  Michigan  and 
the  other  one  east  of  north  toward  the  west  end  of  Lake  Erie.1 
In  other  words,  the  axis  forms  a  Y,  with  the  stem  crossing  the  Ohio 
River  near  Cincinnati.  In  Ohio  part  of  the  richest  territory  has 
been  found  on  this  arch,  but  in  Indiana  it  does  not  appear  on  the 
summit  of  the  arch,  but  on  the  north  side,  where  the  rock  dips  to 
the  northeast.  The  Trenton  limestone  nearly  everywhere  in  these 
two  States  contains  brine  below  the  oil. 2 

;  Fig.  109  is  a  contour  map  of  the  region  redrawn  from  a  map 
by  Orton,  issued  in  1889.  Sections  are  shown  in  figure  110.  The 
extensions  of  the  fields  since  1889  are  indicated  by  comparison 
with  Fig.  108,  after  a  map  by  Bownocker,  issued  in  1917.  As 
shown  by  these  figures  the  oil  and  gas  are  at  crests  of  the  folds  in 
tr|e  region  near  Findlay  and  on  the  north  slopes  of  the  folds  in 
western  Ohio  and  eastern  Indiana. 

The  fractured  and  dolomitized  Trenton  limestone,  which  con- 
tains the  oil  and  gas,  underlies  the  Utica  shale.  Above  the  Utica 
are  Hudson  River  and  Medina  shales,  then  in  ascending  order  the 
Clinton  limestone  and  the  Niagara  shale  and  limestone.  The 
surface  is  practically  flat,  and  on  anticlines  the  Niagara  crops  out. 
In  general  the  gas  lies  about  950  to  1,200  feet  deep,  and  the  oil  a 
little  deeper,  and  both  are  near  the  top  of  the  Trenton  or  generally 
not  more  than  100  or  200  feet  down  in  it. 

The  Trenton  in  the  producing  region  has  a  high  porosity,  which, 
according  to  Orton,  has  been  developed  by  dolomitization  of  lime- 
stone. He  cites  many  analyses  to  show  that  the  Trenton  where 
oil-bearing  is  much  richer  in  magnesium  than  where  it  is  barren  of 
oil.  Orton's  opinion  of  the  origin  of  the  fractures  in  the  Trenton 
limestone  was  not  shared  by  Phinney,3  who  maintained  that  the 

^ORTON,  EDWARD:  Ohio  Geol.  Survey,  vol.  6,  p.  46,  1888. 

ORTON,  EDWARD:  The  Trenton  Limestone  as  a  Source  of  Petroleum  and 
Inflammable  Gas  in  Ohio  and  Indiana.  U.  S.  Geol.  Survey  Eighth  Ann. 
Rept.,  part  2,  pp.  475-662,  1889. 

2BowNOCKER,  J.  A. :  Op.  cit.,  p.  672. 

PHINNEY,  A.  J. :  The  Natural-Gas  Field  of  Indiana.  U.  S.  Geol.  Survey 
Eleventh  Ann.  Rept.,  part  1,  p.  617,  1891. 


APPALACHIAN,  LIMA-IND.,  AND  MICH.  FIELDS  253 

cavities  in  the  Trenton  limestone  are  due  to  "loss  of  substance  and 
not  to  substitution"  in  the  Indiana  field.  He  says  the  rock  is 
commonly  hard,  uniform  in  texture,  and  compact  between  the 
irregular  ramifying  cavities  and  pores  interspersed  through  it. 

Around  the  gas  field  salt  water  rises  to  nearly  equal  altitudes 
on  all  sides.  Although  the  Trenton  is  porous  on  both  sides  of  the 
arch  over  northern  and  central  Indiana,  in  the  southeastern  part 
of  the  State  it  is  more  compact.  The  main  body  of  the  arch  may 
be  regarded,  then,  as  a  long  inverted  bifurcating  trough  having  its 


_ri~(         ^s^^^fe 


LAJtE 
ERIJS 


FIG.  Ill . — Outline  geological  map  of  southern  peninsula  of  Michigan.  (After 
Smith).  Section  from  Manistee  through  Petrolia,  Ontario,  is  shown  on  Fig.  112. 
Roman  numerals  refer  to  formations  listed  on  page  255. 


south  end  closed  and  its  north  ends  immersed  in  the  salt  water, 
which  is  forced  up  into  and  around  it  by  the  hydrostatic  pressure 
of  the  water.  Orton  and  also  Phinney  state  that  the  pressure  is 
due  to  the  pressure  of  the  water  around  the  sides  of  the  arch. 
The  Cincinnati  arch  is  a  dome  surrounded  by  a  larger  basin.  The 
water  descends  down  the  slopes  of  the  basin  and  rises  in  the  arch , 


254 


GEOLOGY  OF  PETROLEUM 


pushing  oil  and  gas  ahead  of  it,  and  equilibrium  is  established  by 
the  back  pressure  of  gas  when  it  equals  the  water  pressure. 

MICHIGAN  FIELD 

The  southern  peninsula  of  Michigan  is  structurally  a  great 
basin  (Fig.  Ill)  whose  long  axis  trends  north.1  The  country  is 
nearly  everywhere  deeply  covered  with  glacial  drift,  and  informa- 
tion pertaining  to  the  underlying  strata  is  obtained  chiefly  from 
well  drillings.  The  area  was  a  seat  of  deposition  through  nearly 
all  of  the  Paleozoic  era,  and  strata  from  the  Ordovician  to  Penn- 
sylvanian  crop  out  or  are  discovered  in  drill  holes.  Shales  are 
abundant  in  the  section,  limestones  are  numerous,  and  a  few  beds 
of  sand  are  present.  In  the  eastern  part  of  the  peninsula  small 


FIG.  112.  —  Diagrammatic  cross-section  of    the    Michigan  basin  from  Port 
Rowan,  Ontario,  to  Manistee,  Michigan.  (After  Smith.) 

folds  are  probably  developed  on  the  westward-dipping  beds  (Fig. 
112).  At  Port  Huron  oil  is  obtained  from  the  Dundee  formation 
(Onondaga  or  "Corniferous"),  which  is  chiefly  limestone.  This 
formation  is  also  the  source  of  oil  in  Lambton  County,  Ontario, 
east  of  Port  Huron.  (See  p.  476.)  The  Port  Huron  wells  have 
produced  oil  since  1900,  but  the  yield  has  never  been  large  and  in 
1919  was  only  a  few  barrels  a  day.  The  oil  of  Michigan  is  of  good 
grade  and  rich  in  the  lighter  spirits.  Gas  and  salt  water  are 
associated  with  it. 

Michigan  Geol. 


,  R.  A.  :  The  Occurrence  of  Oil  and  Gas  in  Michigan. 
and  Biol.  Survey  Pub.  14,  Geol.  ser.  11,  pp.  1-281,  1914. 


APPALACHIAN,  LIMA-IND.,  AND  MICH.  FIELDS255 

PENNSYLVANIAN : 

I.  Saginaw  formation  (upper  Pottsville)  and  Parma  sandstone  (lower  Pottsville). 

MISSISSIPPIAN: 

II.  Grand  Rapids  group:  Upper  Grand  Rapids,  Bayport  or  Mazville  limestone  (upper 
St.  Louis),  and  lower  Grand  Rapids  of  Michigan  series. 

III.  Marshall  formation:  (Kinderhook  of  Iowa,  Black  Hand  and  Logan  of  Ohio.)  Upper 
Marshall  or  Napoleon  and  lower  Marshall. 

IV.  Cold  water  shale  and  Berea  sandstone. 

DEVONIAN: 

V.  Antrim  shale. 

VI.  Traverse  formation  (Hamilton  and  Marcellus,  Erian  and  Delaware  of  Ohio). 
VII.  Dundee  limestone  (Corniferous  and  Schoharie,  Ulsterian,  and  upper  Heidelberg). 

SILURIAN: 

VIII.  Monroe  formation:  Upper  Monroe  or  Detroit  River  series,  middle  Monroe  or  Sylvan" 

ian,  and  lower  Monroe  or  Bass  Island  series. 
IX.  Niagara  (Guelph  and  Lockport),  Rochester  shale,  and  Clinton. 


CHAPTER  XVI 
ILLINOIS 

Introduction.— The  Illinois  output  of  petroleum  and  gas  comes 
mainly  from  the  southeastern  part  of  the  State,  nearly  all  of  it 
from  a  district  including  parts  of  Clark,  Cumberland,  Lawrence, 
^Jasper,  Crawford,  and  Wabash  Counties  (Figs.  113,  114,  115). 
Although  petroleum  was  known  in  Illinois  at  an  earlier  date,  com- 
mercial quantities  were  not  discovered  until  1905.  The  maximum 
yield  was  reached  three  years  later,  when  Illinois  produced 
33,686,238  barrels.  Production  has  declined  rapidly  since  then, 
and  in  1917  the  state  yielded  but  15,776,860  barrels.  Illinois  had 
in  1917,  as  estimated  by  Kay,1  230  square  miles  of  oil-producing 
territory.  The  oil  is  of  high  gravity  and  relatively  free  from  sul- 
phur. 

Most  of  Illinois2  is  covered  with  glacial  drift  and  surface  indi- 
cations of  oil  or  gas  are  meager.  Near  Chicago  bitumen  is  found 
in  the  Niagara  limestone,  and  in  Calhoun  County  there  is  an  oil 
seep  in  that  formation.  Neither  of  these  regions  supplies  petro- 
leum. In  the  first  producing  field  the  evidences  were  obtained 
by  deep  drilling  for  coal  and  by  chance  prospecting.  In  the 
Sandoval  dome,  in  Marion  County,  oil  seeps  along  a  fault  into  a 
coal  mine.  Most  of  the  recent  discoveries  have  resulted  from 
drilling  areas  mapped  and  recommended  by  the  Illinois  State 
Geological  Survey. 

k    The  principal  oil-bearing  strata  are  in  the  Mississippian  and 
\Pennsylyanian  series.     These  series  consist  of  sandstones,  shales, 
and  limestones,  and  there  are  six  or  more  productive  "sands"  in 
the  principal  oil  fields. 

The  sands  are  variable,  some  of  them  attaining  a  thickness  of 
more  than  100  feet  in  places,  but  the  producing  part  is  generally 
but  a  small  percentage  of  the  total  thickness.  The  different  lenses 

JKAY,  F.  H. :  Oil  Fields  of  Illinois.  Geol.  Society  America  Bull,  vol.  28, 
pp.  655-666,  1917. 

2BLATCHLEY,  R.  S.  i  Oil  Resources  of  Illinois,  with  Special  Reference  to  the 
Area  Outside  the  Southeastern  Fields.  Illinois  State  Geol.  Survey  Bull. 
16,  1910;  Oil  in  Crawford  and  Lawrence  Counties.  Illinois  Geol.  Survey 
Butt.  22,  1913. 

256 


ILLINOIS 


257 


of  the  Robinson  sand  in  Crawford  County  average  about  25  feet 
in  thickness,  whereas  the  "pay"  sand  averages  only  about  7  feet. 
In  two  of  the  pools  the  sand  ranges  from  25  to  40  feet  and  is  sat- 
urated with  oil  throughout,  but  this  condition  is  exceptional. 

TOTAL  PRODUCTION  OF  ILLINOIS  SANDS  FOR  TYPICAL  AREAS  TO  JAN.  1,  1917 

(After  Kay) 


Sand 

Depth  (Feet) 

Period  (Years) 

Barrels 

Casey                    

350 

10 

f  5,  309.93 

Robinson 

900 

9 

\2,919.37 
719.14 

Bridgeport.      .  ,    

800-1,150 

9 

8,390.49 

Buchanan  
Kirkwood     

1,150-1,350, 
1,350-1,650* 

10 
9 

36,233.98 
2,546.22 

McClosky          

1,750-2,000 

8 

15,672.80 

Structure  sections  of  Illinois  are  shown  in  Figs.  114  and  115. 
SECTION  FOR  THE  AREA  LYING  SOUTH  OF  A  LINE  DRAWN  EASTWARD  FROM 

THE    MOUTH    OF    THE    MISSOURI    RlVER    TO    MARSHALL,    ILLINOIS,    AND    THE 

STATE  LINE 
(After  Bain,  with  Some  Additions  and  Changes  after  Kay.  Made  by  W.  H.  E.) 

Quaternary : 

Glacial  till,  sand,  and  gravel;  loess  and  alluvium.     Present  as  surface- 
rocks  everywhere  except  in  northwest  and  extreme  south.     Thickness, 
30  to  225+  feet. 

Tertiary: 

Lafayette,  LaGrange  and  Porters  Creek.  Clays,  sands,  gravel,  and 
ferruginous  conglomerate.  Occurs  only  in  extreme  south.  Thickness 
250  feet. 


Occurs  only  in  extreme  south      Thickness  20 


Cretaceous: 

Ripley.     Clay  and  sand, 
to  40  feet. 

Pennsylvanian : 

McLeansboro  formation.     Shales,  sandstones,  thin  limestones  and  coals. 

Rocks  above  top  of  Herrin  (No.  6)  coal.     Thickness  500  to  1,000  feet. 
Carbondale  formation.     Coals,  shales  and  sandstones.     Rocks  between 

the  base  of  Murphysboro  (No.  2)  coal  and  the  top  of  the  Herrin  coal. 

Thickness  about  300  to  350  feet. 
Pottsville  formation.     Sandstone,  some  thin  shales,  and  coals.     Thick> 

ness  500  to  600  feet. 


258 


GEOLOGY  OF  PETROLEUM 


FIG.  113. — Map  showing  oil  and  gas  fields  of  Illinois.  Sections  along  lines 
A  A  and  BB  are  shown  on  Fig.  114.  Districts  are  numbered  as  follows: 
1,  Colmar;  2,  Pike  County;  3,  Carlinville;  4,  Staunton;  5,  Greenville;  6,  Main 
Illinois  field;  7,  Carlyle;  8,  Sandoval;  9,  Sparta;  10,  Litchfield, 


ILLINOIS 


259 


•!•§' 


II  ., 


"ranosrnw" 


260  GEOLOGY  OF  PETROLEUM 

Mississippian: 

Chester.  Sandstones,  shale,  and  limestones  in  series,  with  unconformities 
at  bases  of  sandstones.  At  many  places  six  such  series  are  shown. 
Thickness  varies;  at  several  places  about  300  feet,0 

Cypress.  Sandstone,  very  irregular  and  usually  thin  in  southeastern 
Illinois.  The  Cypress  sandstone  is  absent  in  the  oil  fields  of  Law- 
rence County. 

Unconformity. 

Ste.  Genevieve.  Limestone,  mostly  ooolitic  and  very  cross-bedded. 
Thickness,  80  to  100  feet. 

St.  Louis  and  Salem  (Spergen).  Limestone,  dense  becoming  oolitic  in 
lower  division.  Thickness  300  feet. 

Osage  (Burlington,  Keokuk  and  Warsaw).  Shale  above  and  coarse- 
grained limestone  with  chert  below.  Thickness  440  feet. 

Kinderhook.     Shale  and  shaly  limestone,  red.     Thickness  60  feet. 

Devonian : 

Upper  Devonian  (Sweetland  Creek).     Shale.     Thickness  50  to  60  feet. 

Hamilton.     Limestone.     Thickness  about  100  feet. 

Onondaga  (Grand  Tower).     Limestone.     Thickness  155  feet. 

Upper  Oriskany  (Clear  Creek).     Chert  and  limestone.     Thickness  200 

to  240  feet. 
Helderberg  (New  Scotland).     Limestone.     Thickness  165  feet. 

Silurian: 

Alexandrian  (Sexton  Creek,  Edgewood,  Girardeau  and  Orchard  Creek). 
Limestone  and  shale.  Thickness  116  feet. 

Ordovician: 

Richmond     (Cincinnatian).     Thebes    sandstone,     Fern  vale    limestone. 

Thickness  about  100  feet. 
Kimmswick-Plattin     (Trenton).     Nondolomitic     limestone.     Thickness 

510  feet  recorded. 

St.  Peter.     Sandstone.     120  feet  recorded. 
Prairie  du  Chien  group.     Mostly  dolomitic  limestone  with  occasional 

thin  layers  of  sand  and  shale.     545  feet  recorded. 

"WELLER,  S.:  The  Chester  Series  in  Illinois,  Jour.  Geol  Vol.  28,  p.  408,  1920. 

The  producing  sands  of  Illinois,  as  stated  by  Kay,1  range  in  age 
from  the  top  of  the  Carbondale  formation  of  the  Pennsylvanian 
series  down  to  the  upper  part  of  the  Trenton  limestone.  The 
output  is  derived  principally  from  the  sandstones  of  the  Carbon- 
dale  and  Pottsville  formations  of  the  Pennsylvanian  and  the 
Chester  group  and  Ste.  Genevieve  formation  of  the  Mississippian. 
A  sandstone  at  the  base  of  the  Niagaran  produces  some  oil  at  Col- 
mar,  McDonough  County,  in  western  Illinois. 

'KAY,  F.  H.:  Oil  Fields  of  Illinois.  Geol,  Soc.  America  Bull,  vol.  28,  pp. 
655-666,  1917. 


ILLINOIS  261 

The  producing  beds  are  sands  with  the  exception  of  the  so-called 
McClosky  sand,  which  is  in  reality  the  oolitic  Ste.  Genevieve  lime- 
stone, lying  immediately  beneath  the  Chester  group.  Of  all  the 
producing  beds  in  the  State,  those  of  the  Chester  are  the  most 
regular.  The  sands  of  the  Pennsylvanian  are  extremely  irregular 
in  thickness  and  character,  and  it  is  often  impossible  to  correlate 
them  from  one  well  to  another  with  certainty.  The  Hoing  sand, 
at  the  base  of  the  Niagaran  in  the  Colmar  field,  is  found  in  smaller 
areas  than  any  other  producing  sand.  It  was  deposited  in  depres- 
sions on  the  Maquoketa  surface  during  the  encroachment  of  the 
Niagaran  sea.  Outside  of  the  small  area  at  Colmar  numerous 
drill  holes  in  the  western  part  of  Illinois  have  discovered  it,  but  it 
is  productive  only  in  the  Colmar  field. 

Structurally  Illinois  is  a  spoon-shaped  basin,  the  tip  lying  in  the 
northwest  corner  and  the  deepest  part  of  the  bowl  in  Wayne, 
Edwards',  Hamilton,  and  White  Counties,  in  the  southeast  corner. 
(Fig.  113.)  The  long  axis  of  the  spoon  extends  northwestward, 
parallel  to  the  main  oil  fields.  In  the  western  and  central  parts  of  j 
Illinois  the  dip  toward  the  axis  of  the  basin  is  commonly  as  low  as 

10  feet  to  the  mile.     From  the  main  fields  to  the  basin  the  dip  is 
more  pronounced.     On  the  sides  of  the  basin  there  are  longitudinal  / 
folds.     The  most  prominent  is  the  La  Salle  anticline,  which  runs 
from  Freeport  to  a  point  just  east  of  La  Salle,  and  thence  through 
the  main  oil  field  and  into  Indiana.     From  western  Illinois  the 
rocks  dip  gently  eastward  to  the  Duquoin  anticline.     At  the 
southern  part  of  the  basin  the  dips  of  the  rocks  into  the  basin  are   . 
locally  100  feet  or  more  to  the  mile.     East  of  the  main  oil  fields  in 
Crawford  and  Lawrence  Counties  the  strata  rise  gently  in  Indiana. 
In  southern  Illinois  strong  folds,  faults,  and  igneous  intrusions  are 
present. 

Crawford,  Lawrence,  and  Adjoining  Counties. — The  principal 

011  fields  in  Illinois  are  in  Crawford,  Lawrence,  Clark,  Cumberland, 
and  Wabash  Counties,1  in  the  southeastern  part  of  the  State. 
This  field,  which  was  discovered  in  1905,  yielded  oil  very  near  the 
surface  and  was  developed  rapidly,  reaching  its  maximum  produc- 
tion three  years  after  discovery.     In  the  northern  part  of  the  field 
wells  reached  producing  sands  at  depths  of  about  300  feet.     The 

^LATCHLEY,  R.  S. :  Oil  in  Crawford  and  Lawrence  Counties.  Illinois  State 
Geol.  Survey  Bull.  22,  1913. 


262  GEOLOGY  OF  PETROLEUM 

rocks  that  crop  out  in  this  field  are  of  the  Pennsylvanian  series,  and 
the  oil  is  derived  from  the  Pennsylvanian  and  Mississippian  rocks. 

Broadly  considered,  accumulation  has  taken  place  at  the  south- 
east end  of  the  plunging  La  Salle  anticline.  The  dip  of  the  beds 
to  the  southeast  along  the  axis  of  the  anticline  is  comparatively 
high.  The  lowest  producing  stratum,  the  McClosky  "sand"  of 
the  Ste.  Genevieve  limestone,  lies  within  350  feet  of  the  surface  at 
the  northwest  end  of  the  Clark  County  field,  whereas  in  the 
Lawrence  County  district  it  ranges  in  depth  from  1,700  to  about 
1,860  feet.  Minor  warpings  extend  from  the  La  Salle  anticline 
both  east  and  west.  As  shown  by  contour  maps  drawn  by 
Blatchley,  the  structure  is  very  irregular.  There  are  seven  pro- 
ductive sands,  and  the  contour  maps  for  each  sand  present  note- 
worthy differences.  The  rocks  as  a  general  rule  are  saturated  with 
salt  water,  and  the  oil  and  gas  accumulate  on  anticlines  and  ter- 
races. The  gas  is  rich  in  gasoline,  which  is  recovered,  but  the  gas 
production  is  comparatively  small. 

The  crest  of  the  La  Salle  anticline  in  Crawford,  Lawrence,  and 
adjoining  counties  is  very  irregular.  The  part  of  the  arch  con- 
taining oil  is  2  to  8  miles  wide,  and  nearly  50  miles  long.  On  the 
flanks  of  the  fold  the  field  is  marked  off  by  lines  of  salt  water.1 
Some  of  the  wells,  particularly  those  in  the  McClosky  "sand," 
were  gushers. 

The  Robinson  pool  in  Crawford  County  is  about  7  miles  wide, 
but  narrows  southwest  of  Robinson.  The  Crawford  County  pools 
possess  one  general  oil-producing  zone,  the  Robinson  sand,  which 
is  of  Pennsylvanian  age,  lying  at  the  top  of  the  Pottsville.  This 
sand  is  very  irregular  in  distribution  and  ranges  in  thickness 
between  2  and  50  feet,  the  average  being  25  feet.  At  some  places 
the  Robinson  sand  is  a  series  of  lenses  with  many  streaks,  tongues, 
and  detached  portions.  The  arch  on  which  the  oil  is  found  is  very 
irregular,  with  an  undulating  top  and  a  mapped  closure  of  about 
100  feet.  Although  the  sands  are  irregular  in  distribution  and  at 
places  impervious,  the  yield  has  been  large.  According  to  Blatch- 
ley,2 of  2,370  wells  mapped  in  this  area  all  but  206  yielded  oil  or 
gas.  The  initial  daily  production  was  between  1  and  1,600  barrels. 

The  field  extends  southward  into  Lawrence  County,  which  con- 
tains its  most  productive  portion.  Oil  or  gas  occurs  in  the  Bridge- 

^LATCHLEY,  R    S.  \  Op.  tit.,  p.  143. 

*Idcm,  p.  100. 


ILLINOIS 


263 


port  and  Buchanan  sands  of  the  Pennsylvanian  and  in  the  Gas, 
Kirkwood,  Tracey,  and  McClosky  sands  of  the  Mississippian. 
Blatchley  has  contoured  each  of  these  sands  over  the  most  pro- 
ductive portion  of  the  Lawrence  field.  The  McClosky  sand  does 
not  produce  oil  throughout  the  length  of  the  field,  because  of  local 
irregularities  in  structure  and  the  variable  nature  of  the  producing 
stratum.  It  is  variable  in  thickness  and  averages  not  more  than 
10  feet  over  the  entire  field.  Instead  of  being  a  single  bed,  it  is 
probably  a  zone  in  the  upper  part  of  the  Ste.  Gene  vie  ve  formation, 
the  position  of  the  oil  being  controlled  by  the  porosity  of  the  rocks. 
Within  the  zone,  which  has  a  maximum  thickness  of  80  feet,  one 


6£{0W  SEA 

looo  rr. 

- 

^    / 

- 

SeC.  39 

t 


FIG.  116. — Section  across  dome  in  oil  field  in  Petty  township,  Lawrence 
County,  Illinois.  The  surface  of  the  ground  is  about  1,000  feet  above  the  top 
of  the  section.  (After  Blatchley.) 


to  three  oil  horizons  are  reported.  Toward  the  north  the  sands 
play  out  or  become  thin  and  unproductive.  At  the  south  end  of 
the  oil  field  the  structure  of  the  McClosky,  Tracey,  and  Kirkwood 
sands  is  different  from  that  of  the  Buchanan  and  Bridgeport. 
(See  Fig.  116.)  The  thickness  of  the  beds  between  the  sands  varies 
from  place  to  place,  and  there  is  probably  an  unconformity  near 
the  base  of  the  Buchanan. 

In  the  northern  part  of  Clark  County  the  Trenton  has  yielded 
oil  at  a  depth  of  2,200  feet. 


264  GEOLOGY  OF  PETROLEUM 

The  Allendale  field1  is  in  Wabash  County,  8  miles  southwest  of 
the  Lawrence  County  field.  Oil  was  discovered  here  in  1912. 
The  first  solid  rocks  penetrated  are  the  Pennsylvanian,  which  con- 
sist of  a  series  of  shales  alternating  with  sandstones  and  thin  lenses 
of  limestone.  The  sandstones  and  shales  occur  in  beds  of  varying 
thickness,  ranging  from  only  a  few  feet  to  200  feet  or  more.  At 
the  base  of  the  Pennsylvanian  is  the  Potts ville  sandstone.  The 
Chester  group,  of  Mississippian  age,  consists  of  a  series  of  thin 
limestones  and  shales  with  a  few  thin  beds  of  sandstone,  which 
increase  in  thickness  toward  the  base  of  the  section  penetrated  by 
the  wells.  The  producing  sand  in  the  Allendale  field,  commonly 
known  as  the  Biehl  sand,  has  been  correlated  with  the  Buchanan 
sand  of  the  Potts  ville.  The  oil  is  found  in  a  low  dome  at  about 
1,500  feet  below  the  surface. 

Central  and  Western  Illinois. — In  the  Illinois  Basin,  well  up  on 
its  sides,  the  Potts  ville  rocks  are  saturated  with  salt  water.  In 
the  west-central  part  of  the  State,  however,  a  few  small  .domes 
produce  commercial  quantities  of  gas  and  a  little  oil.  Of  these,  the 
Staunton  gas  field,  the  Carlinville  oil  and  gas  field,  and  the  Litch- 
field  oil  and  gas  field  are  the  most  important.  In  these  fields  oil 
and  gas  are  found  in  lenses.  Four  productive  horizons  have  been 
recognized,  separated  by  small  vertical  intervals.  Theoretically,  a 
tilted  porous  sandstone  lens  should  provide  conditions  for  accumu- 
lation of  oil  and  gas  at  its  upper  end ;  but  in  Illinois,  as  stated  by 
Kay,  the  bedding  planes  of  the  Pottsville  seem  generally  not  im- 
pervious enough  to  prevent  the  lateral  movement  of  oil  and  gas 
unless  doming  of  the  strata  has  capped  the  edge  of  the  porous  bed 
and  prevented  escape  of  the  oil. 

The  oil  and  gas  field  near  Carlinville,  Macoupin  County, 2  is  one 
of  small  production.  All  the  rocks  belong  to  the  coal  measures, 
which  consist  of  shales,  sandstones,  a  minor  amount  of  limestone, 
and  several  beds  of  coal.  Three  persistent  beds  are  recognized — 
the  Carlinville  limestone,  coal  No.  6,  and  the  oil  and  gas  zone  at 
the  base  of  the  Pennsylvanian.  The  intervening  shales,  although 
fairly  constant  in  thickness,  are  changeable  in  character.  Under- 
neath the  sands  the  drill  usually  strikes  limestone,  which  is  sup- 

iRicn,  J.  L. :  The  Allendale  Oil  Field.  Illinois  Geol.  Survey  Bull.  31,  pp. 
59-68,  1915. 

2KAY,  F.  H. :  The  Carlinville  Oil  and  Gas  Field.  Illinois  Geol.  Survey  Bull 
20,  pp.  83-95,  1915. 


ILLINOIS  265 

posed  to  be  either  the  Ste.  Genevieve  or  the  St.  Louis  limestone, 
of  Mississippian  age.  The  Chester  shales,  sandstones,  and  lime- 
stones, which  underlie  the  area  south  of  Carlinville  and  which 
include  most  of  the  producing  sands  of  the  main  oil  fields,  are 
absent  in  this  field.  Although  the  productive  sands  are  not  invar- 
iably found  at  the  same  stratigraphic  position,  they  lie  near  the 
base  of  the  coal  measures  and  are  believed  to  constitute  the  Potts- 
ville  formation. 

Gas  has  accumulated  at  the  top  of  the  dome,  oil  occurs  below 
the  gas,  and  salt  water  lies  below  the  oil. 

The  first  valuable  deposit  of  oil  found  in  Illinois  was  discovered 
near  Litchfield  by  the  Litchfield  Coal  Co.  in  November,  1879. 
In  an  effort  to  find  a  lower  coal  seam  sufficiently  thick  to  be  profit- 
ably mined,  a  hole  was  drilled  in  the  bottom  of  the  shaft  which 
passed  into  oil-bearing  sand  at  a  depth  of  225  feet  below  the  coal 
and  682  feet  below  the  surface.  Salt  water  at  first  threatened  to 
floojl  the  mine,  but  the  hole  was  plugged,  though  oil  leaked  into 
the  mine  and  was  skimmed  from  the  mine  water  for  several  years. 
The  oil  was  a  heavy  lubricating  oil  and  was  associated  with  gas. 
The  structure  of  the  rocks  of  the  area  near  Litchfield  as  indicated 
by  that  of  the  Herrin  (No.  6)  coal  shows  a  distinct  dome.  The 
production  of  oil  has  not  been  large.  1 

The  oil  pool  at  Carlyle,  in  Clinton  County,  southwestern  Illinois, 
about  45  miles  east  of  St.  Louis,  was  discovered  early  in  April, 
19  II.2  The  oil  is  found  in  the  Carlyle  sand,  which  belongs  to 
the  Chester  group  (Mississippian).  The  Carlyle  sand  js  on  the 
whole  a  soft,  porous  sandstone  of  irregular  thickness.  Around  the 
edges  of  the  pool  it  is  harder  than  in  the  center,  and  in  one  or  two 
places  it  pinches  out.  Above  the  sand  is  about  30  feet  of  bluish 
shale  containing  locally  red  shale.  Above  the  Chester  is  the  Potts- 
ville,  which  carries  salt  water  and  locally  gas;  this  is  overlain  by 
Pennsylvanian  sandstone,  shale,  limestone,  and  coal.  The  oil 
sand  is  practically  horizontal.  Outside  the  field  the  sand  dips  in 
all  directions  except  north,  and  apparently  it  also  pinches  out  in 
all  directions  except  to  the  north. 


,  WALLACE  :  Oil  and  Gas  in  the  Gillespie  and  Mount  Olive  Quadrangles, 
Illinois.     Illinois  Geol.  Survev  Bull.  31,  pp.  71-107,  1915. 

2SnAw,  E.  W.  :  Carlyle  Oil  Field  and  Surrounding  Territory.     Illinois  Geol. 
Survey  Bull  20,  pp.  43-80,  1915. 


266 


GEOLOGY  OF  PETROLEUM 


The  Greenville  gas  field1  is  in  Bond  County,  about  2  miles  south 
of  Greenville.  The  gas  has  accumulated  in  the  crest  of  an  anti- 
cline that  is  elongated  in  an  east-west  direction.  It  is  found  in  two 
sands  belonging  to  the  Chester  group — the  Lindley  No.  1  and 
Lindley  No.  2.  These  sands  are  separated  by  a  few  feet  of  shaly 
strata,  and  Chester  shales  lie  above  the  Lindley  No.  1.  The  top 
of  the  dome  is  about  50  feet  high,  which  is  somewhat  above  the 
elevation  shown  in  the  Herrin  (No.  6)  coal.  The  fold  has  increased 
with  depth. 


FEET 
400 


200 


100 


1  mile 


FIG.  117. — Diagram  showing  unconformities  and  spotted  character  of  Hoing 
sand  in  Colmar  field,  Illinois.  (After  Morse  and  Kay.) 

The  Colmar  oil  field,  in  western  Illinois,  was  discovered  in  1914. 
The  existence  of  a  dome  was  first  pointed  out  by  Hinds  from  levels 
run  on  coal  No.  2,  which  crops  out.  Oil  was  found  in  a  sandstone 
at  the  base  of  the  Niagaran,  which  was  probably  deposited  in 
depressions  on  the  Maquoketa  surface  during  the  encroachment  of 
the  Niagaran  sea.  The  sand  occurs  as  lenses  separated  by  areas 
in  which  the  limestone  lies  directly  on  the  shale  with  no  interven- 

^LATCHLEY,  R.  S. :  Oil  and  Gas  in  Bond,  Macoupin,  and  Montgomery 
Counties,  Illinois.  Illinois  Geol.  Survey  Bull  28,  p.  45,  1914. 


ILLINOIS 


267 


GENERALIZED  SECTION  OF  ROCKS  IN  COLMAR  OIL  FIELD  AND  SURROUNDING 
TERRITORY     (After  Morse  and  Kay) 


System 

Series 

Drillers' 
Interpre- 
tation 

Formation 

Character 

Thickness 

Quaternary. 

Surface. 

Alluvium;  confined  to  valleys. 
Loess;    most    conspicuous    along 
bluffs  of  Illinois  River. 
Drift;   mixed   clay,   sand,  gravel, 
and  boulders. 

Feet 
Variable. 
0-75 

Average,  25. 
In  filled  val- 
leys, 100  +. 

' 

Pennsylvanian. 

Coal-rearing 
formations. 

Carbondale. 

Principal  coal-bearing  formation 
of  Illinois.  Shales,  sandstones, 
thin  beds  of  limestone,  clay  and 
coal. 

0-140  + 

Pottsville. 

Unconformity. 
St.  Louis. 
Unconformity  . 

Salem. 
Unconformity  . 
Warsaw. 

Includes  beds  from  base  of  coal 
No.  2  to  Mississippian.  Sand- 
stone and  shale,  and  some  lime- 
stone, clay,  and  thin  coal. 

0-140 

Mississippian. 

o> 
_£ 

1 

Limestone,  brecciated,  blue, 
weathers  yellow  in  places;  con- 
tains scattered  corals. 

0-30  + 

[mpure  limestones  of  yellow  tint, 
difficult  to  distinguish  from 
limy  sandstone;  at  places  shale 
increases  and  the  formation  con- 
sists of  limy  shales,  limy  sand- 
stone, and  impure  limestone. 

30* 

Thin-bedded  impure  limestone  and 
shales,  fossiliferous.  Consider- 
able blue  clay  shale  is  locally 
present. 

30* 

Keokuk. 

Gray  crystalline  limestone,  fossilif- 
erous, shaly  toward  top. 

30  + 

Burlington. 

Limestone,  generally  cherty;  not 
exposed. 

? 

Kinderhook. 
Unconformity  . 

Unconformity  . 
Hamilton. 
Unconformity. 

Unconformity  . 
Richmond. 
(Maquoketa) 
Unconformity  . 

Kimmswick- 
Plattin. 
(Trenton) 

Shale,  bluish  gray,  limy. 

100* 

Devonian. 

Ms 

Shale,  light  to  dark;  many  spores 
of  Sporangites,  a  minute  reddish 
fossil. 

100* 

V 

s 

Limestone,  gray,  small  amount  of 
sand,  and  some  pyrite.  Usually 
not  magnesian. 

15-30 

Silurian. 

1 
I 

Limestone,  gray,  crystalline,  mag- 
nesian. Exists  in  separate  len- 
ticular masses;  where  it  is  not 
present.  Hamilton  rests  on  Ma- 
quoketa shale.  Show  of  oil  in 
places  near  base. 

0-20 

Hoing    oil 
sand. 

Sandstone,  quartzitic;  grains  well 
rounded.  In  lenses  with  no  con- 
nection. Probably  accumulated 
in  depressions  on  Maquoketa 
surface.  Producing  bed  of  Col- 
mar field. 

0-25 
(Average      in 
Colmar 
field  14). 

1 

Shales,  bluish  green. 

180-200 

Limestone,  gray,  white,  or  brown. 
Crystalline  in  places.  Odor  of 
oil  not  unusual.  Not  magnesian 
in  Colmar  field. 

300-400 

St.  Peter. 

Sandstone;  generally  saturated 
with  mineral  water. 

145-225 
recorded. 

268  GEOLOGY  OF  PETROLEUM 

ing  sand.  As  stated  by  Kay,  no  direct  connection  is  apparent 
between  the  Hoing  pool,  where  the  sand  lies  90  feet  above  sea  level 
on  a  terrace  at  the  northeast  side  of  the  dome,  and  the  Hamm  pool, 
on  top  of  the  dome,  where  the  sand  is  70  feet  higher.  The  pool  at 
the  town  of  Colmar1  lies  on  the  north  side  of  the  dome  and  prob- 
ably has  no  direct  connection  in  the  sand  with  either  of  the  other 
pools. 

The  Hoing  sand,  which  carries  the  oil,  is  as  much  as  14  feet  thick 
where  present  but  is  very  erratic  in  occurrence.  The  lenses  are 
surrounded  by  impervious  beds.  The  oil  pool  lies  on  the  flat  part 
of  the  oil  sand  on  the  side  of  a  low  dome  and  is  associated  with  salt 
water.  Several  domes  have  been  discovered  by  contouring  the 
base  of  coal  No.  2,  but  the  production  is  small.  The  anticline  in 
the  Canton-  A  von  region  has  been  described  by  Savage.2  '(See 
Fig.  117). 

At  Sandoval,  Marion  County,  a  few  miles  north  of  Centralia, 
a  dome  has  been  contoured  mainly  by  using  data  obtained  in  coal 
mining.  This  dome  and  an  associated  terrace  yielded  oil  and  gas 
in  two  sands  below  the  coal.  The  area  is  faulted,  and  the  oil  was 
first  noted  at  a  seep  into  a  mine  through  a  fault. 

Near  Sparta,  in  Randolph  County,  western  Illinois,  gas  and  a 
little  oil  are  found  in  the  Chester  (Mississippian).  The  gas  occurs 
along  a  small  synclinal  fold,  but  the  relations  are  uncertain.  The 
field  has  produced  little  oil  and  is  not  now  important.3 

In  Pike  County,  western  Illinois,  4  gas  was  discovered  by  drilling 
wells  for  water.  The  gas  occurs  along  an  anticline,  the  eastern 
limb  of  which  is  determined  by  the  line  separating  the  productive 
from  the  dry  wells.  The  porous  stratum  forming  the  reservoir  is 
a  bed  of  yellowish-brown  magnesian  limestone  which  probably 
belongs  to  the  Niagara.  The  thick  bed  of  Kinderhook  shales  that 
overlies  the  Niagara  limestone  in  this  region  'provides  the  imper- 


HENRY:  Oil  and  Gas  in  the  Colchester  and  Macomb  Quadrangles. 
Illinois  Geol.  Survey  Bull.  23  (extract),  pp.  11-13,  1914. 

^SAVAGE,  T.  E.:  Geologic  Structure  of  Canton  and  Avon  Quadrangles. 
Illinois  Geol.  Survey  Bull.  33,  pp.  91-99,  1916. 

3BLATCHLEY,  R.  S.  i  Illinois  Geol.  Survey  Bull.  16,  p.  146,  1910. 

RAVAGE,  T.  E.  :  The  Pike  County  Gas  Field.  Illinois  Geol.  Survey  Bull. 
2,  pp.  78-87,  1906. 

WORTHEN,  A.  H.  :  Illinois  Geol.  Survey,  vol.  4,  pp.  24-42,  1870. 


ILLINOIS  269 

vious  cover  of  the  reservoir.  The  wells  are  all  shallow,  the  gas 
being  reached  at  depths  of  75  to  350  feet,  depending  largely  upon 
the  inequalities  of  the  surface.  The  production  is  small. 

GEOLOGIC  FORMATIONS  OF  PIKE  COUNTY  GAS  FIELD 
(After  Worthen) 

Feet 

Pleistocene:  Loess  and  drift 0-100 

Pennsylvanian 20-60 

Mississippian: 

St.  Louis  limestone <0-30 

Keokuk  group  (limestone  and  shale) 100-125 

Burlington  limestone 150-200 

Kinderhook  group  (mainly  shale) 100-120 

Niagara  limestone , 0-50 

References  to  Illinois  Fields 

BARRETT,  N.  O.:  Petroleum  in  Illinois  in  1917  and  1918.  Illinois  Gcol. 
Survey  Bull.  40,  pp.  1-144,  1919. 

BLATCHLEY,  R.  S.:  Oil  Resources  of  Illinois.  Illinois  Geol.  Survey  Bull 
16,  pp.  42-176,  1910. 

Oil  and  Gas  in  Crawford  and  Lawrence  Counties.     Illinois  Geol. 

Survey  Bull  22,  1913. 

Oil  and  Gas  in  Bond,  Macoupin,  and  Montgomery  Counties. 

Illinois  Geol.  Survey  Bull  28,  1914. 

KAY,  F.  H. :  Carlinville  Oil  and  Gas  Field.  Illinois  Geol.  Survey  Bull  20, 
pp.  81-95,  1915. 

Petroleum  in  Illinois  in  1914  and  1915.     Illinois  Geol.  Survey 

Bull  33,  pp.  71-90,  1915. 

Petroleum  in  Illinois  in  1914  and  1915.     Illinois  Geol.  Survey 

Bull.  33,  pp.  71-90,  1916. 

Notes  on  the  Bremen  Anticline.     Illinois  Geol.  Survey  Bull. 

33,  pp.  101-103,  1916. 

Oil  Fields  of  Illinois.     Geol.  Soc.  America  Bull,  vol.  28,  pp. 

655-666,  1917. 

KIRK,  C.  F.:  Natural  Gas  in  the  Glacial  Drift  of  Champaign  County. 
Illinois  Geol.  Survey  Bull.  14,  pp.  272-275,  1909. 

LEE,  WALLACE:  Oil  and  Gas  in  Gillespie  and  Mount  Olive  Quadrangles. 
Illinois  Geol.  Survey  Bull.  31,  pp.  71-107,  1915. 

MORSE,  W.  C.,  and  KAY,  F.  H. :  Area  South  of  the  Colmar  Oil  Field.  Illinois 
Geol.  Survey  Bull.  31,  pp.  7-35,  1915. 

The  Colmar  Oil  Field— a  Restudy.     Illinois  Geol.  Survey  Bull. 
31,  pp.  37-55,  1915. 

RICH,  J.  L.:  The  Allendale  Oil  Field.  Illinois  Geol.  Survey  Bull.  31,  pp, 
57-68,  1915, 


270  GEOLOGY  OF  PETROLEUM 

RICH,  J.  L.:  Oil  and  Gas  in  the  Birds  Quadrangle.     Illinois  Geol.  Survey 
Bull.  33,  pp.  105-145,  1916. 

Oil  and  Gas  in  the  Vincennes  Quadrangle.     Illinois  Geol.  Sur- 
vey Bull.  33,  pp.  147-175,  1916. 

.  SHAW,  E.  W. :  The  Carlyle  Oil  Field  and  Surrounding  Territory.     Illinois 
Geol.  Survey  Bull  20,  pp.  43-80,  1915. 

UDDEN,  J.  A.,  and  SHAW,  E.  W. :  U.  S.  Geol.  Survey  Geol  Atlas,  Belle  ville- 
Breese  folio  (No.  195),  p.  14,  1915. 

UDDEN,  JON:  Coal  Deposits  and  Possible  Oil  Fields  Near  Duquoin.     Illinois 
Geol.  Survey  Bull  14,  pp.  254-262,  1909. 

WELLER,  STUART:  Anticlinal  Structure  in  Randolph  County.     Illinois  Geol. 
Survey  Bull  31,  pp.  69-70,  1915. 


CHAPTER  XVII 
MID-CONTINENT  FIELDS 

/  J"  tef-£rd£tz. 

General  Features. — The  Mid-Continent  oil  fields  include  the 
oil-producing  areas  of  Oklahoma,  Kansas,  and  Missouri,  the  gas- 
producing  region  of  Arkansas,  and  the  fields  of  northern  and  central 
Texas  and  northern  Louisiana.  The  principal  producing  areas 
are  in  Kansas,  Oklahoma,  and  northern  Texas  and  Louisiana.  In 
these  fields  oil  is  found  mainly  in  Carboniferous  and  Cretaceous 
strata.  In  the  principal  fields  of  Kansas  and  northern  Oklahoma 
the  sand  members  associated  with  Cherokee  shales  produce  nearly- 
all  the  oil.  In  southern  Oklahoma  and  northern  Texas  near  Red 
River  oil  is  obtained  from  sandstones  of  the  Pennsylvanian  and 
from  sandstones  that  are  correlated  with  the  Permian  (Red  Beds) 
by  some  investigators  and  with  the  upper  Pennsylvanian  by  others. 
These  beds  produce  gas  and  oil  in  the  Healdton  and  neighboring 
districts.  In  the  Ranger  region,  northern  Texas,  oil  is  found  in  the 
Bend  series  (Mississippian).  In  east  central  Texas  and  northern 
Louisiana  oil  is  found  in  Cretaceous  sandstones  and  chalks. 

In  the  Mid-Continent  fields  oil  and  gas  occur  on  domes,  anti- 
clines, structural  noses,  structural  terraces,  and  fluted  monoclines. 
On  the  whole  the  structural  features  are  somewhat  less  accentuated 
than  those  in  the  Appalachian  oil  fields,  and  the  porous  rocks  -are 
more  generally  filled  with  salt  water.  The  oil  saturation  is  greater 
than  in  most  other  fields,  and  structural  elevations  with  less  than 
twenty  feet  of  closure  are  searched  for  diligently  and  explored. 

The  major  uplifts  in  this  region  (Fig.  118)  are  the  Ozark  dome, 
the  Ouachita  orographic  element,  including  the  Ouachita,  Ar- 
buckle,  and  Wichita  mountains,  the  Llano-Burnet  uplift  of  Texas, 
and  the  Sabine  uplift.  Although  the  Ouachita  element  is  more 
highly  deformed  than  the  Ozark  dome,  the  structure  of  the  Ozark 
is  more  far-reaching,  for  the  beds  dip  westward  far  away  from  the 
Ozark  center,  and  southwestward  within  a  comparatively  short 
distance  of  the  Ouachita  element. 

The  Ozark.  uplift  is  a  low  dome  with  rudely  elliptical  outline, 
lying  in  southern  Missouri,  northern  Arkansas,  southeastern 

271 


272 


GEOLOGY  OF  PETROLEUM 


Kansas,  and  northeastern  Oklahoma.     As  stated  by  Siebenthal1 
it  is  roughly  bounded  on  the  north  and  northeast  by  Missouri  and 


£ LiUiUiiiii; 


FIG.  118. — Sketch  map  showing  geology  of  region  containing  Mid-continent 
oil  field.  The  Pennsylvania!!  outcrops  in  the  areas  shown  by  dots,  widely 
spaced.  There  are  small  outcrops  of  Silurian  and  Devonian  rocks  in  the 
Ozark  region.  These  are  not  shown  in  the  sketch.  The  igneous  rocks  which 
are  in  the  areas  represented  by  small  crosses,  are  older  than  the  sedimentary 
rocks. 


SIEBENTHAL,  C.  E.:  Origin  of  the  Zinc  and  Lead  Deposits  of  the  Joplin 
Region,  Missouri,  Kansas,  and  Oklahoma.  U.  S.  Geol,  Survey  Bull.  606, 
p.  23,  1915, 


MID-CONTINENT  FIELDS  273 

Mississippi  Rivers,  on  the  west  by  Spring  and  Neosho  (Grand) 
Rivers,  on  the  west  and  south  by  Arkansas  River,  and  on  the  south- 
east by  Black  River  and  some  of  its  tributaries.  The  uplift  as  a 
whole  is  a  table-land  bounded  by  long,  low  northern  and  western 
slopes  whose  inclination  is  generally  imperceptible  to  the  eye,  and 
for  much  of  its  extent  by  an  abrupt  southern  slope  facing  the  open 
valley  of  Arkansas  River.  Near  and  parallel  to  its  southern  mar- 
gin the  uplift  culminates  topographically  in  the  Boston  Mountains, 
a  long,  narrow  plateau  rising  to  an  elevation  of  2,000  feet.  The 
plains  that  surround  the  uplift  have  a  general  altitude  of  500  to  750 
feet.  The  central  portion  of  the  Ozarks  is  an  upland  lying  some- 
what below  the  crest  of  the  Boston  Mountains. 

The  Ozark  uplift  is  a  broad  anticline  in  which  the  strata  have  no 
perceptible  inclination  except  at  the  southern  margin,  where  the 
Boston  Mountains  break  off  into  a  southward-dipping  monocline. 
Superimposed  upon  the  uplift  are  quaquaversal  domes,  of  which 
the  principal  one  is  in  the  region  of  the  St.  Francis  Mountains. 

In  the  early  history  of  the  Ozark  region  parts  of  the  crystalline 
rocks  of  the  St.  Francis  Mountains  were  islands  in  an  archipelago, 
and  their  erosion  furnished  the  material  that  formed  the  Cambrian 
and  Ordovician  sandstones,  and  which,  with  that  which  formed 
the  associated  dolomitic  limestones,  was  spread  out  over  Missouri 
and  the  adjacent  States.  Silurian  limestones  and  shales  were 
deposited  on  the  southern  and  northeastern  margins  of  the  Ozark 
region,  but  in  the  western  part  of  the  region  there  was  no  Silurian 
sedimentation.  During  Devonian  time  limestone  was  deposited 
on  the  northern  and  eastern  borders  of  the  region  and  sandstone 
on  the  southern  border.  The  Chattanooga  shale  of  the  Devonian 
series  underlies  a  triangular  area  in  northwestern  Arkansas,  south- 
western Missouri,  and  northeastern  Oklahoma.  After  the  Devon- 
ian period  the  Ozark  region  was  submerged  and  the  Mississippian 
limestones  were  laid  down  probably  over  the  whole  area.  Eleva- 
tion and  erosion  followed,  during  which  the  limestone  land  surface 
developed  a  sinkhole  topography.  This  land  was  in  turn  sub- 
merged and  upon  its  irregular,  bouldery,  cherty  surface  was  laid 
down  a  series  of  shales  and  sandstones  of  Pennsylvanian  age,  the 
lowest  series  being  the  Cherokee  shale,  which  contains  the  principal 
oil  sands  of  Kansas  and  Oklahoma.  Until  the  end  of  Pennsylvan- 
ian time  the  crystalline  area  of  the  St.  Francis  Mountains  was  the 
stratigraphic  nucleus  of  the  Ozark  region.  At  the  end  of  the 


274 


GEOLOGY  OF  PETROLEUM 


FIG.  119. — Index  map  of  Oklahoma,  showing  mountain  areas  and  certain  oil 

fields. 


MID-CONTINENT  FIELDS  275 

Carboniferous  period  the  Ozark  region  was  raised  almost  to  its 
present  position,  the  highest  place  coinciding  closely  with  the 
geographic  center.  The  uplifted  area  has  since  been  subjected 
to  minor  warping. l 

The  Ouachita  orographic  element  (Fig.  119)  extends  from  east 
to  west  through  western  Arkansas  and  southern  Oklahoma  for  a 
distance  of  350  miles.  This  element  may  be  subdivided  into  the 
Ouachita  Mountains,  the  Arbuckle  Mountains,  and  Wichita 
Mountains.  None  of  these  mountains  are  very  high — indeed,  the 
Boston  Mountains,  which  lie  north  of  and  parallel  to  the  Ouachita 
Mountains  on  the  Ozark-monocline  are  higher  than  any  part  of  the 
Ouachita  element  or  the  Missouri  Ozarks.  The  Ouachita  element 
is,  however,  a  center  of  close  folding  and  is  topographically  for  the 
most  part  a  plateau  rather  than  a  mountain  range.  It  represents 
the  eroded  remnant  or  roots  of  what  was  once  probably  a  contin- 
uous lofty  range. 

The  Ouachita  Mountains  of  Arkansas  and  eastern  Oklahoma  are 
joined  to  the  Arbuckle  Mountains  of  Oklahoma  by  a  broad  area  of 
folded  rocks,  and  the  two  mountainous  regions  form  structurally 
a  single  feature.  In  the  Ouachita  Mountains  Paleozoic  sedi- 
ments, including  those  as  late  as  Mississippian,  are  highly  de- 
formed. In  Arkansas2  they  are  closely  folded  and  in  places 
overturned.  In  eastern  Oklahoma3  they  are  folded  and  also  pro- 
foundly faulted.  The  Arbuckle  Mountains,  in  their  eastern  part, 
where  they  coalesce  with  the  plain,  are  only  about  750  feet  above 
the  sea,  but  their  elevation  increases  westward  to  1,300  feet.  The 
structural  trend  is  about  N.  70°  W. 

The  Arbuckle  Mountain  region  contians  a  thick  series  of  rocks, 
chiefly  limestones,  which  range  from  Middle  Cambrian  to  Devon- 
ian. These  are  succeeded  on  the  borders  by  an  almost  equal 
thickness  of  Carboniferous  conglomerates,  shales,  and  sandstones. 
In  the  central  part  of  the  district,  unconformably  beneath  the 
Cambrian  strata,  there  is  a  mass  of  granite,  granite  porphyry, 
diabase,  and  associated  crystalline  rocks.  Most  of  uplifting  and 
folding  of  the  region  occurred  before  the  deposition  of  the  Permian 

^lEBENTHAL,  C.  E.  I  Op.  tit.,  pp.   11-12. 

2SiMONDS,  F.  W.,  and  BRANNER,  J.  C. :  Arkansas  Geol.  Survey  Rept.  for 
1888,  vol.  4,  p.  xiii,  1891. 
»TAFF,  J.  A. :  U.  S.  Geol.  Survey  Geol  Atlas,  Coalgate  folio  (No.  74),  1901, 


276  GEOLOGY  OF  PETROLEUM 

Red  Beds,  which  were  laid  down  across  its  western  part,  but  in 
places  the  Red  Beds  themselves  are  distinctly  folded. 

About  60  miles  to  the  northwest  are  the  Wichita  Mountains, 
which  are  physiographically  in  marked  contrast  to  the  Arbuckle 
plateau,  being  composed  of  a  range  of  rugged  mountains  and 
straggling  peaks  and  hills,  standing  in  a  level  plain.  The  Wichita 
uplift  trends  N.  70°  W.  approximately  in  the  same  direction  as  the 
Arbuckle  uplift.  It  consists  of  a  central  mass  of  igneous  rocks, 
which  is  partly  surrounded,  unconformably,  by  a  thick  section  of 
Cambrian  and  Ordovician  sandstone  and  limestone.  The  strati- 
graphy is  essentially  similar  to  that  of  the  Arbuckle  uplift. l  The 
Cambrian  and  Ordovician  strata,  approximately  6,000  feet  thick, 
bear  no  evidence  that  they  were  either  folded  or  uplifted  into  land 
at  any  time  during  their  deposition.  The  main  Arbuckle  uplift 
began  near  the  middle  and  culminated  near  the  end  of  PennsyK 
vanian  time,  prior  to  the  deposition  of  the  Red  Beds.  The  Red 
Beds  are  only  gently  folded  between  the  Arbuckle  and  Wichita 
Mountains. 

The  Criner  Hills,  which  lie  15  miles  south  of  the  Arbuckle 
Mountains,  consist  of  a  faulted  block  of  Paleozoic  strata  about 
7  miles  long,  which  trends  northwest.  Structurally  they  are  sim- 
ilar to  the  Arbuckle  Mountains  and  they  include  the  same  Pale- 
ozoic strata.  As  stated  by  Taff , 2  they  are  the  Arbuckle  Mountains 
in  miniature. 

Briefly  stated  the  deformation  of  the  Ouachita- Arbuckle- Wichita 
region  has  taken  place  during  three  periods.  These  are  (1)  Pre 
Pennsyl vanian,  (2)  Post  Pennsyl vanian,  and  (3)  Post  Permian' 
In  the  Arbuckle  region  the  major  folding  was  Pre  Pennsyl  vanian,3 
although  in  the  Ardmore  district  south  of  the  Arbuckles,  the  Penn- 
sylvanian  rocks  are  highly  tilted.  North  of  the  Arbuckles  also 
they  are  rather  closely  folded.  There  are  also  considerable  de- 
formation of  the  Ouachita  Mountains  in  Post  Pennsylvanian  time. 

Since  Permian  and  also  since  Cretaceous  time,  minor  warpings 
have  taken  place  in  the  Mid-Continent  fields,  for  strata  of  both 
Pennsylvanian  and  Cretaceous  age  are  folded.  Dips  as  great  as 

^AFP,  J.  A.:  Preliminary  Report  on  the  Geology  of  the  Arbuckle  and 
Wichita  Mountains.  U.  S.  Geol.  Survey  Prof.  Paper  31,  p.  11,  1904. 

2TAFF,  J.  A.:  Op.  tit.,  pp.  47-50. 

3FuLLER,  M.  L. :  Carbon  Ratios  in  Carboniferous  Coals  of  Oklahoma  and 
Their  Relations  to  Petroleum.  Econ.  Geology,  vol.  15,  pp.  187-224,  1920. 


MID-CONTINENT  FIELDS  277 

5°  have  been  noted  on  the  limestones.  In  Cotton  County,  south- 
east of  Healdton,  Oklahoma,  according  to  Wegemann,1  the  adjust- 
ment of  minor  streams  to  folds  is  very  exact,  and  it  is  possible  that 
movements  have  continued  till  comparatively  recent  times. 

The  Llano-Burnet  region  of  central  Texas  lies  on  the  broad 
coastal  slope  that  extends  from  the  Cordillera  to  the  Gulf  of 
Mexico.2  In  this  region  erosion  has  exposed  rocks  of  pre-Cam- 
brian  and  Paleozoic  age  within  and  about  the  rim  of  an  oval 
topographic  basin  which  is  nearly  surrounded  by  Cretaceous  rocks. 
The  Llano-Burnet  region  is  a  structural  uplift.  It  exhibits  the 
remnants  of  an  ancient  mountain  range  that  has  been  eroded. 
The  influence  of  this  uplift  is  reflected  by  the  rock  structure  far  to 
the  north  of  the  Llano-Burnet  region. 

The  rocks  of  the  Llano-Burnet  region  fall  into  three  subdivisions 
— (1)  pre-Cambrian  schists,  gneisses,  and  granites;  (2)  Paleozoic 
sandstones,  limestones,  and  shales;  and  (3)  Cretaceous  sandstones, 
clays,  and  limestones.  The  Paleozoic  strata,  which  completely 
surround  the  pre-Cambrian  area,  are  folded  and  faulted  and  are 
separated  from  the  pre-Cambrian  by  an  unconformity  representing 
a  great  time  interval.  The  Cretaceous  formations  are  nearly  flat. 
They  are  separated  from  the  Paleozoic  rocks  by  a  great  erosional 
unconformity. 

The  Llano-Burnet  region  has  been  one  of  elevation  and  erosion 
through  long  geologic  periods.  The  pre-Cambrian  rocks  were 
eroded  almost  to  base-level,  and  on  them  were  deposited  Cambrian 
and  Ordovician  rocks.  The  Silurian,  Devonian,  Jurassic,  and 
Triassic  are  lacking,  showing  probably  that  during  much  of  Pale- 
ozoic time  the  region  was  above  the  sea.  Near  the  end  of  the 
Paleozoic  era  and  before  the  Mesozoic  rocks  were  deposited,  fold- 
ing and  faulting  took  place  on  a  considerable  scale.  The  Mesozoic 
rocks,  which  lie  on  the  Paleozoic  strata,  are  generally  nearly  hori- 
zontal in  the  Llano-Burnet  region. 

The  Mid-Continent  fields  produce  oil  of  high  gravity  as  is  shown 
by  the  following  analyses: 

WEGEMANN,  C.  H. :  Anticlinal  Structure  in  Parts  of  Cotton  and  Jefferson 
Counties,  Oklahoma.  U.  S.  Geol.  Survey  Bull.  602,  p.  34,  1915. 

2PAiGE,  SIDNEY:  Mineral  Resources  of  the  Llano-Burnet  Region,  Texas. 
U.  S.  Geol.  Survey  Bull.  450,  1911.  See  also  U.  S.  Geol.  Survey  Geol.  Atlas, 
folio  (No.  183),  1912. 

HILL,  R.  T. :  Physical  Geography  of  the  Texas  Region.  U.  S.  Geol.  Survey 
Topographic  folio  (No.  3),  1900. 


278  GEOLOGY  OF  PETROLEUM 

ANALYSES  OF  OILS  OF  MID-CONTINENT  FIELDS" 


Field 

Baume 
Gravity 

Gasoline,  Benzine, 
Naphtha,  Kerosene, 
0-300°  C. 
(Per  Cent) 

Lubricating 
Oil  and 
Residuum 
(Per  Cent 

KANSAS 

Chanute  

fTJ.l 

39.5 

57  2 

Paola 

34  5 

43 

55  8 

Augusta  . 

38.3 

53.6 

46 

OKLAHOMA 

Muskogee  

38.1 

46 

52.8 

Gushing.  . 

40  9 

66 

30 

Bird  Creek  

34.8 

45.5 

52.8 

Glenn  Pool. 

35  5 

50.5 

49.9 

Healdton  

30.3 

42 

52.9 

TEXAS 

Petrolia  (deep)  

44.9 

35 

65 

Petrolia  (shallow)  

39  5 

19 

81 

Electra  (deep) 

42 

28  5 

71.5 

Electra  (shallow).  ... 

40.8 

25 

75 

Corsicana  (light)  

36.3 

50 

50 

Corsicana  (heavy)  

25.9 

55  (kerosene) 

45 

Thrall.  .  . 

38  4 

55 

45 

Strawn  

36.3 

51 

49 

LOUISIANA 

Caddo  

41 

58 

40.4 

Crichton  

39.8 

67 

33 

°GABDNEB,  J.  H.:  The  Mid-Continent  Oil  Fields.  Geol.  Soo.  America  Bull,  vol.  28,  p.  719, 
1917. 

In  general  the  crude  petroleum  of  Kansas  and  Oklahoma  is  dark 
green  by  reflected  light,  brownish  by  transmitted  light,  and  has  a 
Baume  gravity  of  about  34°.  Muskogee  furnishes  oils  that  are 
yellowish  green  in  reflected  light  or  bright  wine-colored  in  trans- 
mitted light  and  run  as  high,  as  38°  Baume.  The  Madill  yields  an 


MID-CONTINENT  FIELDS  279 

oil  that  has  a  dark  olive  color  in  reflected  light  or  dark  wine  color  in 
transmitted  light  and  runs  as  high  as  47.5°  Baume.  From  Garber 
and  Ingalls  are  obtained  green  oils  of  43°  Baume.  Petroleum  of 
slightly  inferior  grade  comes  from  the  Healdton  field.  It  is  a  very 
dark  oil,  with  an  average  Baume  gravity  of  about  30°,  and  runs 
somewhat  low  in  its  content  of  light  distillates.  Petroleums  from 
the  deeper  sands,  as  at  Gushing  and  Blackwell,  Oklahoma,  or  at 
Augusta,  Kansas,  average  between  35°  and  40°  Baume  and  run 
relatively  high  in  gasoline  and  other  light  products.  Petroleums 
from  the  Petrolia  and  Electra  fields,  Texas,  have  a  dark-brown 
color  in  reflected  light,  and  range  from  39°  to  45°  Baume  but  are 
not  so  high  in  many  of  the  light  distillates  as  petroleums  from  Kan- 
sas and  Oklahoma.  Petroleum  from  the  Thrall  field  of  Texas  is 
rather  light  in  gravity  and  has  a  brownish  color  somewhat  similar 
to  that  of  the  better  grades  at  Corsicana  and  Moran,  Texas,  or  at 
Caddo,  Louisiana.  Local  areas  in  Texas,  as,  for  instance,  the 
Brownwood  district,  furnish  petroleum  running  low  in  gravity  and 
high  in  lubricating  constituents,  resembling  in  this  respect  oil  from 
the  Healdton  field,  although  of  lower  gravity. 

Although  the  Mid-Continent  petroleums  are  rarely  free  from 
asphalt,  this  constituent  is  present  in  very  small  quantity,  ranging 
from  practically  nothing  to  5  per  cent. 1 

NORTHEASTERN  OKLAHOMA,  SOUTHEASTERN  KANSAS, 
ARKANSAS,  AND  MISSOURI 

General  Statement. — The  northeastern  Oklahoma  and  south- 
eastern Kansas  fields  are  treated  as  a  structural  and  stratigraphic 
unit.  East  of  the  area  which  includes  them,  extending  from  north- 
ern Missouri  almost  to  Muskogee,  Oklahoma,  are  found  Missis- 
sippian  and  older  rocks.  From  Muskogee  County,  east  and  south- 
west to  the  Arbuckle  Mountains  is  an  area  containing  many  gas 
fields,  of  which  it  is  said  that  any  oil  present  may  have  been  vapor- 
ized or  scattered  by  metamorphism  attending  the  faulting  of  the 
Ouachita  element  (Fig.  76,  p.  176).  West  of  this  area  in  Oklahoma 
and  Kansas  the  petroliferous  rocks  are  covered  by  Permian  beds, 
and  in  that  direction  limits  to  the  oil  fields  can  not  be  set.  On 
account  of  the  great  depth  of  the  oil  sands,  the  character  of  the 
Permian  beds,  and  the  smaller  amount  of  folding  of  the  Permian, 
the  structure  is  difficult  to  interpret,  and  development  is  not  rapid. 

GARDNER,  J.  H.:  Op.  dL,  p.  718. 


280  GEOLOGY  OF  PETROLEUM 

Nevertheless  the  field  is  being  slowly  and  laboriously  extended 
westward.  In  northeastern  Kansas  Pennsylvanian  rocks  are  found, 
but  the  territory  is  not  known  to  be  petroliferous. 

The  rocks  that  crop  out  in  the  area  are  Pennsylvanian  and  lower 
Permian.  The  beds  strike  about  N10°-20°  E.  and  dip  west  about 
30  feet  to  the  mile.  Locally  the  dip  increases,  and  on  folds  it 
becomes  100  feet  to  the  mile  or  more.  Reverse  dips  are  rarely 
more  than  1°.  Faulting  is  common  east,  southeast,  and  south  of 
the  district.  Faults  are  not  rare  in  the  Oklahoma  portion  of  the 
oil-bearing  area  also,  but  as  a  rule  the  displacement  of  the  faults 
is  very  small.  On  the  whole  deformation  in  the  region  is  not 
intense. 

The  oil  and  gas  are  found  in  sands  and  very  subordinately  in 
thin-bedded  porous  limestones.  Most  of  the  productive  sands  are 
in  the  Cherokee  shale  series,  above  the  Mississippian.  Recently 
some  oil  has  been  found  in  the  Mississippian  limestone  and  in 
sands  below  it.  The  shales  of  the  Cherokee  are  generally  dark 
colored  or  black  and  carry  bands  of  highly  bituminous  material. 

The  Bartlesville  sand  is  by  far  the  most  productive,  having 
supplied  90  per  cent  or  more l  of  the  oil  produced  in  Oklahoma  and 
Kansas  up  to  1919.  It  is  a  gray  to  brown  sandstone,  containing 
usually  a  small  amount  of  lime  carbonate,  enough  to  effervesce  in 
acid.  In  the  Bartlesville  region  it  is  from  30  to  60  feet  thick.  It 
has  an  average  porosity  of  20  per  cent.  The  thickest  sands  do 
not  contain  oil  in  large  quantities.  McCoy2  states  that  the  pay 
sands  where  thickest  show  many  partings  of  black  shale. 

Oil  and  gas  seeps  are  very  rare  in  this  area,  and  at  most  pools 
they  are  lacking.  East  of  the  oil-bearing  region,  however,  in 
southeastern  Kansas,  southwestern  Missouri,  and  northeastern 
Oklahoma,  the  Cherokee  is  marked  at  many  places  by  asphalt 
bodies  or  oil  seeps.  Salt  water  is  generally  associated  with  the  oil. 

The  Permian  beds  contain  gas  on  the  Blackwell  anticline,3  on 
the  Garber  dome,  and  on  the  Billings  anticline.  In  the  area  where 
the  Permian  crops  out  the  Pennsylvanian  carries  oil  near  the  top. 

GARDNER,  J.  H.:  Mid-Continent  Geology.  Oil  and  Gas  Journal  SuppL, 
May  30,  1919. 

2McCoY,  A.  W. :  Notes  on  Principles  of  Oil  Accumulation.  Jour.  Geology, 
vol.  27,  p.  252,  1919. 

3GARDNER,  J.  H. :  Mid-Continent  Oil  Fields.  Geol.  Soc.  America  Butt. 
vol.  28,  p.  699,  1917. 


MID-CONTfNENT  FIELDS  281 

Oil  residues  are  found  in  Oklahoma  in  Ordovician,  Carboniferous 
and  Cretaceous  rocks. 

The  location  of  the  fields  in  Oklahoma  is  shown  by  Fig.  120. 

In  the  northeastern  Oklahoma  and  southeastern  Kansas  field 
the  larger  number  of  oil  and  gas  bearing  districts  are  on  low  domes 
or  low  anticlines,  although  a  considerable  number  are  on  terraces. 
At  least  four  are  developed  in  lenses.  Some  of  the  productive 
folds  are  isolated  structural  features  with  clearly  defined  bound- 
aries, like  the  domes  of  the  Gushing  field,  Garber,  and  many  others. 
Other  fields  are  located  on  zones  of  gentle  crumpling,  like  the 
Bartlesville  area  in  Osage  County  and  the  areas  in  Washington 
County,  to  the  east  of  it.  Although  these  folds  are  gentle,  many 
of  them  are  easily  recognized  on  account  of  numerous  exposures. 
In  many  of  the  districts  there  is  an  abundance  of  salt  water  under 
strong  pressure.  In  such  districts  the  oil  and  gas  lie  above  the 
water.  Where  the  sands  lie  deep,  segregation  is  more  pronounced. 

OKLAHOMA 

Salient  Features. — Oklahoma  has  produced  a  much  greater  pro- 
portion of  the  oil  recovered  from  the  Oklahoma-Kansas  field  than 
Kansas.  The  production  in  Oklahoma  has  come  mainly  from 
Nowata,  Washington,  Osage,  Kay,  Rogers,  Tulsa,  Pawnee,  Garfield, 
Wagoner,  Creek,  Muskogee,  and  Okmulgee  Counties.  In  the  eastern 
part  of  the  field  the  oil  is  obtained  from  shallower  wells  than  in  the 
western  part,  where  the  Cherokee  series  lies  below  great  thick- 
nesses of  Pennsylvanian  or  of  Pennsylvanian  and  Permian  strata. 
In  the  eastern  part  of  the  field  the  pools  are  not  all  related  to 
clearly  defined  folds,  although  production  is  generally  controlled 
by  slight  crumples  of  the  strata,  by  terraces,  and  by  warpings. 
In  this  part  of  the  field  the  regional  dip  of  the  Cherokee  is  consid- 
erably lower  than  it  is  in  the  western  part.  In  Osage,  Washington, 
and  Nowata  Counties,  which  lie  along  the  northern  boundary  of 
Oklahoma,  the  dip  is  much  less  than  it  is  in  counties  to  the  south 
and  west.  Apparently  the  oil  traveled  up  the  gradually  flattening 
dip  of  the  beds,  and  much  of  it  lodged  near  tops  of  very  gentle 
folds  and  local  terraces,  where  the  flattening  beds  checked  migra- 
tion. In  the  steeper  part  of  the  monocline,  in  Kay,  Garfield, 
Noble,  Creek,  and  Pawnee  Counties,  the  greater  concentrations 
are  in  clean-cut  anticlines  or  on  definitely  closed  folds  that  are 


282 


GEOLOGY  OF  PETROLEUM 


S  £  £tdOo  ££  (§Q  <X®  W  qOO^StS-Bo  i»< 
^t,«^«ot-co«o;:£,3Si3««:oo20«gJ?;«,o5:;»ooSc,f3S{o^{5«SS5«5^^^52o-S 


FIG.  120. — Index  map  showing  principal  oil  and  gas  fields  in  Oklahoma. 
(Data  from  Shannon,  and  others.) 


MID-CONTINENT  FIELDS  283 

superimposed   upon   the   great   monocline.     Noteworthy   among 
these  features  are  the  Gushing,  Garber,  and  Ponca  City  folds. 

McCoy l  states  that  pools  which  are  not  on  anticlines  or  domes 
show  a  close  relation  to  faults.  Many  of  these  faults  do  not  crop 
out  but  are  revealed  by  comparison  of  drill  records.  Some  of  the 
accumulations  of  oil  appear  to  occur  where  sands  are  sealed  by 
being  faulted  against  shales. 

The  Cherokee  formation,  the  principal  oil  and  gas  producing 
member  of  the  Pennsylvanian  series  in  Kansas  and  northeastern 
Oklahoma,  contains  the  Squirrel,  Skinner,  Red  Fork,  Nemire, 
Bartlesville,  Tucker,  Dutcher,  and  other  sands.  In  some  districts 
five  or  six  sands  are  productive. 

The  Cherokee  formation  in  the  Belton  district,  south  of  Kansas 
City,  Missouri,2  is  about  430  feet  thick.  In  southeastern  Kansas3 
it  is  450  feet  thick.  From  the  Kansas  line  southward  the  Cherokee 
formation  gradually  increases  in  thickness,  so  that  it  is  1,000  feet 
thick  at  Pryor  Creek.  In  Kansas  the  Cherokee  is  above  the 
Mississippian  limestone  and  below  the  Fort  Scott  limestone,  two 
easily  recognized  formations.  Toward  the  south  these  limestones 
disappear,  and  correlations  are  less  certain.  In  the  Muskogee 
quadrangle  the  Winslow  and  Boggy  formations,  1,500  feet  thick, 
are  correlated  by  Taff  with  the  Cherokee,  and  in  his  report  on 
the  Coalgate  quadrangle  he  correlated  the  Atoka,  Hartshorn, 
McAlester,  Savanna,  and  Boggy,  which  have  a  thickness  of 
9,000  feet,  with  the  Cherokee.  The  formations  toward  the 
south  are  overlapped.  The  greater  thickness  of  the  Cherokee 
toward  the  south  is  due  in  part  to  the  overlap,  some  of  the  beds 
being  older  than  the  Cherokee  in  Kansas. 

The  sea  in  which  the  Cherokee  was  deposited  was  probably  sup- 
plied by  sediments  mainly  from  the  Ouachita  region,  the  sediments 
becoming  thicker  to  the  south.  That  the  land  mass  existed  toward 
the  south  in  Pennsylvanian  time  is  obvious  also  from  the  character 
of  the  sediments.  The  great  shale  and  sandstone  formations  of 
Oklahoma  thin  out  or  decrease  in  thickness  toward  the  north, 

^cCoY,  A.  W. :  Notes  on  Principles  of  Oil  Accumulation.  Jour.  Geology, 
27,  p.  262,  1919. 

2 WILSON,  M.  E. :  Oil  and  Gas  Possibilities  in  the  Belton  Area.  Missouri 
Bur.  Geology  and  Mines,  1918. 

3  ADAMS,  G.  L,  GIRTY,  G.  H.,  and  WHITE,  DAVID:  Stratigraphy  and  Paleon- 
tology of  the  Upper  Carboniferous  Rocks  of  the  Kansas  Section.  U.  S.  Geol. 
Survey  Bull.  211,  p.  65,  1903 


284  GEOLOGY  OF  PETROLEUM 

where  the  section  contains  thicker  and  more  numerous  limestone 
members  and  less  sand  and  shale. 

The  Permian  beds,  which  cover  large  portions  of  both  Kansas 
and  Oklahoma,  thicken  rapidly  toward  the  west;  in  Roger  Mills 
County, l  on  the  western  border  of  Oklahoma,  they  are  3,000  feet 
thick.  Between  the  Arbuckle  and  Wichita  mountains  several 
fields  derive  oil  and  gas  from  beds  which  some  class  with  the 
Permian  but  which  others  have  classified  as  Pennsylvanian. 
(See  p.  320.) 

There  are  no  oil  pools  in  the  area  of  outcropping  Mississippian 
and  lower  rocks  in  northeastern  Oklahoma,  nor  in  the  region  of 
older  rocks  south  of  the  Choctaw  fault.  In  the  area  between 
Fort  Smith  and  Coalgate  there  is  a  belt  of  folded  Pennsylvanian 
strata  in  which  several  gas  fields  are  developed  but  which  yield  no 
oil.  This  condition  is  due  to  metamorphism,  according  to  Gard- 
ner,2 who  cites  as  evidence  the  coals  of  this  belt,  which  run  as  high 
as  70  per  cent  carbon  figured  on  an  ash  and  moisture  free  basis. 


GENERAL  STRATIGRAPHIC  SECTION  IN   MAIN  OIL  AND   GAS   DISTRICT  ON 
NORTHERN  OKLAHOMA 

(Compiled  from  Sections  by  Taff,  Aurin  ard  Gardner,  with  Economic  Notes 

Mainly  from  Gardner) 
Permian  series: 

1.  Unclassified  shales,  with  thin  limestone  and  sandstone  mem-  Feet 

bers  ............  .  ................................. 

2.  Herington  limestone  .............................  .....  18-20 

3.  Uncas  shale  ..............  .  ...........................  50 

4.  Winfield  limestone  ....................................  10-15 

5.  Doyle  shale  ..........................................  22-35 

6.  Fort  Riley  limestone  and  other  beds  of  thin  limestone,  sand- 

stone, and  shale  down  to  the  Neva  limestone,  inclusive.0 
Contains  near  base  the  shallow  gas  sands  at  Blackwell, 
Billings,  and  Garber  ................................  500-600 

7.  Elmdale  formation  ;  included  in  Permian  of  Kansas  by  Beede 


,  FRITZ:  Geology  of  the  Red  Beds  of  Oklahoma.     Oklahoma  Geol. 
Survey  Bull.  30,  1917. 

GARDNER,  J.   H.  :  The  Mid-Continent  Oil  Fields.     Geol.   Soc.   America 
Bull,  vol.  28,  p.  699,  1916. 

°BEAL  places  the  base  of  the  Permian  in  the  Cushing  field  50  feet  above  the  top  of  the  Neva 
limestone. 


MID-CONTINENT  FIELDS 


285 


Pennsylvania!!  series: 

Ralston  group:  Limestones  and  shale  beds  of  Kansas  section 
from  Americus  limestone  to  Lecompton  limestone,  inclusive. 
In  Oklahoma  consists  of  red  and  gray  sandstone,  red  shale, 
and  thin  limestones.  Contains  the  Garber  oil  sand. 

1.  Upper  division  down  to  Pawhuska  limestone,  inclusive..  .  650 

2.  Lower  division  down  to  top  of  Elgin  sandstone 140 

Sapulpa  group : 

1.  Elgin  sandstone.     Probable  horizon  of  shallow  oil  sand  in 

the  Newkirk  field  and  at  Ponca  City 20-150 

2.  Oread  limestone 0-20 

3.  Buxton  sandstone  and  shale.     Horizon  of  main  oil  sand  at 

Ponca  City  and  gas  sand  at  Myers 700-1,000 

4.  Avant  limestone 0-10 

£.  Ramona  formation.     Sandstone,  shale,  and  thin  limestone 

beds.     Includes  Lost  City  limestone  and  Musselman  oil 

sands  of  the  Cushing  and  Cleveland  areas 300-400 

6.  Dewey  limestone 15-25 

7    Skiatook  formation;  sandstone,  shale,  and  thin  limestone 
beds.     Includes  Hogshooter  limestone  and  Layton  oil 

sand 350-400 

8.  Lenapah  limestone 10-20 

Tulsa  group: 

1.  Nowata  shale;  includes  Wayside  oil  sand 75-150 

2.  Oolagah  limestone  or  Big  lime  of  the  drillers 20-50 

3.  Labette  shale  (local  coal  bed,  Dawson  coal) 75-100 

4.  Claremore  formation.     Sandstone,  shale,  and  beds  of  thin 
limestone.     Contains  at  the  base  the  Fort  Scott  or  Oswego 

limestone.     Includes  Cleveland  and  Peru  oil  sands 275-350 

Muskogee  group:  Beds  of  shale,  sandstone,  and  thin  limestone 
correlated  with  the  Cherokee  shale  (Boggy  and  Winslow 
formations  at  Muskogee).  Includes  the  main  oil  sands  of 
Oklahoma;  the  Red  Fork,  Bartlesville  (Glenn),  Tucker, 
Taneha,  Booch,  Morris,  and  Muskogee  sands,  the  Muskogee 
lying  at  the  unconformable  base  of  the  Pennsylvanian  series.  450-1,500 

Unconformity 
Mis?issippian  series: 


1.  Morrow  limestonea . 

Unconformity. 

2.  Pitkin  limestone.  . 


100-200 
40-60 


"SMITH  places  the  Morrow  in  the  Glenn  pool  above  the  Mississippian.     (See  p.  293.) 


286 


GEOLOGY  OF  PETROLEUM 


3.  Fayetteville   formation;   sandstone,    shale,    and  limestone. 

Contains  the  Mounds  oil  sand  and  a  deep  sand  near 

Sapulpa 20-200 

Unconformity. 

4.  Boone  formation;  massive  white  limestone  and  massive  beds 

of  chert 200-400 

Devonian  system: 

1.  Chattanooga  formation;  black  fissile  shale 30-50 

2.  Sylamore  sandstone;  clear  quartz  sandstone 0-25 

Unconformity. 

Ordovician  system: 

1.  Tyner  formation;  thin  sandstone  and  limestone  in  shale. . . .          60-100 

2.  Burgen  (St.  Peter)  sandstone;  massive  quartz  sandstone.  . . .  5-100 

Cambrian  system: 

Massive  limestone  beds  shown  in  Harrington  well  at  Joplin, 

Missouri 1,165 

From  Muskogee  southward  the  lower  portion  of  the  Pennsyl- 
vanian  series  and  the  older  rocks  thicken  at  the  rate  of  about  100 
feet  to  the  mile.  The  following  is  the  general  section  for  the 
McAlester-Coalgate-Atoka  region : 


GENERAL    STRATIGRAPHIC    SECTION    IN    EASTERN    OKLAHOMA,  NORTH    OF 

ARBUCKLE  MOUNTAINS 
(After  Sections  by  Taff*  and  Gardner6) 

Lower  portion  of  Pennsylvanian :  Feet 

1.  Seminole  conglomerate 1-50 -f 

2.  Holdenville  shale 260 

3.  Wewoka  formation.     Sandstone  and  shale  with  beds  of 

thin  limestone 500-800 

4.  Wetumka  shale 120 

5.  Calvin    sandstone.     Approximate    horizon    of    Oswego 

limestone  in  northern  area 140-240 

6.  Senora  sandstone 140-485 

7.  Stuart  shale 90-280 

8.  Thurman  sandstone 90-280 

9.  Boggy  shale,  with  beds  of  thin  sandstone;  limestone  and 

thin  irregular  coal  at  base 2,000-2,600 

"TAFP,  J.  H.:  U.  S.  Geol.  Survey  Geol.  Atlas,  Coalgate folio  (No.  74),  1901. 

6GARDNER,  J.  H.:  Mid-Continent  Oil  Fields.     Geol.  Soc.  America  Bull.,  vol.  28,  p.  696,  1917 


MID-CONTINENT  FIELDS  287 

10.  Savanna  sandstone;  massive  sandstone  strata  with  beds 

of  shale  (horizon  of  Bartlesville  sand) 1,000 

11.  McAlester  shale.     Includes  strata  of  sandstone.     Coal 

beds  of  the  McAlester-Coalgate  region  (Oklahoma  coal 

field) 1,800-2,000 

12.  Hartshorn  sandstone 150 

13.  Atoka  formation.     Massive  beds  of  sandstone  with  alter- 

nating beds  of  shale 3,100 

14.  Wapanucka  limestone 100 

Mississippian  series:  Caney  shale 1,500 

Devonian  system :  Woodf ord  chert 600 

Ordovician  and  Silurian  systems:  Sandstone,  shale,  and  lime- 
stone   5,000-7,000 

Cambrian  system :  Reagan  sandstone 100 

Unconformity. 
Pre-Cambrian  granites. 

Gushing  Pool. — The  Gushing1  oil  pool  is  mainly  in  western  Creek 
County  but  extends  westward  into  Payne  County.  The  field 
includes  a  number  of  subdivisions,  among  them  Shamrock,  Drum- 
right,  Dropright,  and  Mount  Pleasant.  The  first  well  in  this  field 
was  drilled  in  1912  by  C.  B.  Shaffer  on  the  Jones  farm,  about  1  mile 
north  of  Drumright.  The  development  was  rapid,  especially  after 
the  discovery  of  oil  and  gas  in  the  Bartlesville  sand.  The  product- 
ion of  the  field  reached  about  300,000  barrels  of  oil  a  day,  and 
at  one  time  about  160,000  barrels  of  oil  was  produced  daily  by  160 
wells  from  the  Bartlesville  sand  alone. 

The  following  table  gives  the  geologic  formations  of  the  Penn- 
sylvanian  series  as  reported  by  Buttram  in  the  vicinity  of  the 
Gushing  field — the  youngest  at  the  top: 

Neva  limestone. 

Sandstones  and  shales  and  thin  limestones  (556.5  feet). 

Pawhuska  limestone  (provisional  correlation).     Is  2,340  feet  above 

Fort  Scott  limestone  and  1,243  to  1,262  feet  above  Lost  City 

limestone. 

Shales  and  sandstones  (134  feet). 
Elgin  sandstone. 

BUTTRAM,  FRANK  :  The  Gushing  Oil  and  Gas  Field,  Oklahoma.  Oklahoma 
Geol.  Survey  Bull  18,  pp.  1-60,  1914. 

BEAL,  C.  H. :  Geologic  Structure  in  the  Gushing  Oil  and  Gas  Field,  Okla- 
homa, and  Its  Relation  to  the  Oil,  Gas,  and  Water.  U.  S.  Geol.  Survey  Bull. 
658,  1917. 


288 


GEOLOGY  OF  PETROLEUM 


Interval. 

Lost  City  limestone. 

Interval  (1,078  to  1,097  feet).     Includes  Lay  ton  sand  at  700  to  810 

feet  above  Wheeler  sand. 

Fort  Scott  or  Oswego  limestones  (75  feet)  (  =  Wheeler  sand). 
Interval. 
Bartlesville  sand  (in  Cherokee  shale.) 

The  most  prominent  outcropping  stratum  is  a  bed  of  limestone 
that  is  probably  in  part  at  least  equivalent  to  the  Pawhuska  lime- 
stone of  northern  Oklahoma. 

Oil  is  produced  from  six  sands,  the  Layton,  Jones,  Wheeler, 
Skinner,  Bartlesville,  and  Tucke'r.  A  sketch  of  the  field  is  shown 
in  Fig.  121  and  a  section  in  Fig.  122. 

The  dominant  structural  feature  in  the  Gushing  field,  as  stated 
by  Beal,  is  a  broad  north-south  anticlinal  fold  (Fig.  123)  with 


Cusht'ny  po  ?/ 


Sapulpa 


I 


G/enn 


FIG.  121. — Sketch  showing  structure  in  Gushing  Pool,  Oklahoma  (after 
Beal}  and  in  Glenn  Pool,  Oklahoma  (after  Smith.)  Contours  show  elevation  of 
Pawhuska  limestone  above  sea  in  Gushing  Pool  and  of  Fort  Scott  or  Oswego 
limestone  below  sea  in  western  part  of  the  Glenn  pool.  Dots  represent  oil 
wells.  Some  scattered  wells  are  not  shown. 

domes  along  its  axis  and  many  subsidiary  folds  and  irregularities 
along  its  sides.  This  great  fold  is  one  of  the  largest  structural 
features  in  northern  Oklahoma.  The  contours  of  the  three  oil 
sands  differ  locally  from  the  contours  of  the  surface  rocks,  although 
the  general  structural  axes  are  practically  identical.  Each  sand 
in  the  field  exhibits  small  irregularities  that  apparently  bear  no 
definite  vertical  relations  to  one  another — for  example,  the  Bartles- 


MID-CONTINENT  FIELDS 


289 


ELEVATION  IN  FEET  OP  HIGHEST  CONTOUR  ON  CRESTS  OP  FOUR  FOLDS  IN  THE 

SURFACE  BED,  THE  LAYTON  SAND,  THE  WHEELER  SAND,  AND  THE  BARTLES- 

VILLE  SAND,  AND  THE  DIP  IN  DIFFERENT  DIRECTIONS  FROM  THE  CRESTS 

(After  Beal;  +,  Above  Sea  Level;   -,  Below  Sea  Level) 


Dropright  Dome 

Shamrock  Dome 

Amount  of  Dip 

Amount  of  Dip 

Eleva- 
tion 

2Yz  Miles 

Eleva- 
tion 

of  Crest 

Northeast 

11A  Miles 

%  Mile 

of  Crest 

1H  Miles 

%  Mile 

of  Crest 

West  of 

East  of 

West  of 

East  of 

Along 

Crest 

Crest 

Crest 

Crest 

Anticline 

Surface  beds.  .  .  . 

+  1  ,050 

100 

150 

125 

+  1  ,125 

135 

60 

Layton  sand.  .  .  . 

400 

225 

175 

"250 

-     325 

325 

250 

Wheeler  sand.  .  .  . 

-1,075 

225 

200 

<*350 

-1  ,150 

175 

200 

Bartlesville  sand  . 

-  1  ,525 

175 

200 

200 

-1,550 

325 

250 

Anticline  in  North- 

Mount Pleasant  Dome 

ern  Part  of  T.  16 

N.,  R.  7  E. 

Amount  of  Dip 

Amount 

Eleva- 

Eleva- 

of Dip 

tion 

of  Crest 

2\i  Miles 
West  of 

4  Miles 
West  of 

%  Mile 
South- 

% Mile 
North- 

tion 
of  Crest 

1A  Mile 
East  of 
Crest 

Crest 

Crest 

west 
of  Crest 

east 
of  Crest 

Surface  beds.  .  .  . 

+  1  ,100 

150 

225 

75 

75 

+  1,050 

50 

Layton  sand.  .  .  . 

275 

300 

425 

325 

325 

-     400 

75 

Wheeler  sand.  .  .  . 

-1,100 

350 

475 

325 

400 

-1,325 

50 

Bartlesville  sand  . 

-1  ,450 

350 

6475 

325 

400 

-1,700 

100 

"Part  of  vertical  distance  estimated. 

ftPart  of  horizontal  and  vertical  distances  estimated. 


290 


GEOLOGY  OF  PETROLEUM 


FEET, 


),ooo- 


1,200- 


1,400- 


1,600- 


2,600- 


Pawhuska  limestone 
Surface  of  ground 

Fresh  water 
Fresh  water 
Fresh  water 


Salt  water 
Saltwater 


Salt  water 


Layton  Iime"(some6as) 

Break 

Layton  sand  (oil; 


Jones  sand 

Cleveland  sand  (some  |a^| 


,er 
s< 


Sandy  member  (oil) 


Skinner  sand 


w 

3?eYerJ 
•r  sand  (oil;  *  water  in  bottori 


FIG.  122. — Generalized  geologic  section 
showing  the  positions  of  oil  and  gas 
sands  in  Gushing  field,  Oklahoma.  (After 
Beat.} 


ville  sand  may  show  a  small 
dome  that  has  no  counter- 
part in  the  Layton  and 
Wheeler  sands. 

The  distribution  of  oil 
and  gas  in  the  sands  indi- 
cates that  the  source  or 
gathering  ground  of  the  oil 
and  gas  was  west  or  north- 
west of  the  field.  The  direc- 
tion they  took  may  be  due 
in  part  to  the  fact  that  the 
dominant  structural  feature 
is  an  anticline  on  a  great 
monocline,  the  fold  having 
a  short  east  limb  and  a  long 
west  limb.  The  gathering 
area  is  therefore  practically 
all  on  the  west  limb.  Gas 
first  fills  up  the  crest  of  the 
fold  and  acts  as  a  barrier 
between  the  water  on  the 
east  side  and  the  oil  migrat- 
ing up  the  west  limb.  The 
oil,  on  account  of  its  slower 
rate  of  movement  through 
porous  rocks,  collects  after 
the  gas  and  forms  a  pool 
against  the  gas  on  the  west 
or  long  limb.  (See  Fig.  123.) 
Below  the  oil  is  salt  water. 
The  plane  between  the  two 
is  not  level,  however,  but  in 
some  sands  the  water  sur- 
faces on  which  the  oil  and 
gas  rest  are  inclined  and  dip 
away  from  centers  of  anti- 
clinal folds. 

In     the     Gushing     field 
proper  there  is  very  little 


MID-CONTINENT  FIELDS 


291 


292 


GEOLOGY  OF  PETROLEUM 


Keel 


e 

CO 

a 

1 
1 

C 

1 

i 

« 

o 

i 

a 
.2 

| 

i 
>> 

0" 

'  ,  '  ,  ' 

200- 
400- 

i          i         r 

600- 
800 

^PP 

1,000- 

—  ,-'     ,    '    i 

1,200- 

1,-tvO- 

1,600- 
1,800- 
2  000 

:i  ;',';•.;  t  ;;*.*::*• 

•H-H-S- 

'£v--xS:-;.:V 

illi 

2,200 

m 

S-'-'-^i 

s^ 

2,400 
2,500 

^^8- 

"Lost  City  limestone."  _       .    . 

(Approximately  850  feet  laultmg' 

below       Tiger       Creek  Quadrangle, 
sandstone.) 

lies    to    the 


In    the    Bristow 
however,    which 
southeast,  there 
are  many  northwest  faults.1 


Checkerboard  lime 


Dawson  coal 


BIB  Hme 


Fort  Scott  limestone 

Sand 

Sand 

Limestone 


Red  Fork  sand 


Sand 
Glonn  sand 

Squaw  sand 

Rhodes  or  Dutchcr  sand, 


Morrow  formation » 

aad  V? 

Pitkin  limestone  ' 


Mounds  sand 


Band 

Boone  limestone  ? 


FIG.  124. — Composite  skeleton  section 
of  the  Glenn  pool  region,  Oklahoma. 

(After  Smith.) 


Glenn  Pool— The  Glenn 
pool2,  which  is  southwest  of 
Tulsa  and  about  30  miles  east 
of  the  Gushing  pool,  is  one  of 
the  most  productive  of  the 
Mid-Continent  field.  It  in- 
cludes several  minor  pools 
known  as  the  Taneha,  Red 
Fork,  and  Ferryman.  The  pool 
was  discovered  in  1906. 

The  westward  dip  of  the 
strata,  which  is  about  50  feet 
to  the  mile,  is  interrupted  by 
areas  in  which  the  formations 
lie  flat  or  nearly  so,  whereas  in 
other  areas  the  dip  is  greater 
than  normal.  The  structure  is 
complicated  also  by  a  system 
of  folds  whose  axes  roughly 
parallel  the  direction  of  gen- 
eral dip — slightly  north  of 
west.  These  folds  are  not  well 
defined  but  are  westward- 
plunging  flutings.  which  merge 

^ATH,  A.  E.:  Structure  of  the 
Northern  Part  of  the  Bristow 
Quadrangle,  Creek  County,  Okla- 
homa, with  Reference  to  Petro- 
leum and  Natural  Gas.  U.  S. 
Geol.  Survey  Bull.  661,  pp.  69-99, 
1918. 

2SMiTH,  C.  D.:  The  Glenn  Oil 
and  Gas  Pool  and  Vicinity,  Okla- 
homa. U.  S.  Geol.  Survey  Bull 
541,  pp.  34-48,  1912. 


MID-CONTINENT  FIELDS  293 

both  to  the  east  and  west  with  the  prevailing  westward-dipping 
monocline. 

The  oil  and  gas  occur  in  the  several  sands  mentioned  below,  the 
field  extending  westward  down  the  monoclinal  dip.  Where  the 
strata  are  fluted  on  the  monocline  the  wells  are  closely  spaced  on 
the  minor  warpings  of  the  strata.  Both  upward  and  downward 
flutings  carry  oil.  The  monocline  is  believed  to  be  sealed  possibly 
by  tighter  sands  above  the  productive  portion  of  the  field,  or  by 
shales  coming  together  where  sands  play  out. 


SECTION  SHOWING  FORMATIONS  EXPOSED  IN  AND  TO  THE  EAST  OP  THE  GLENN 
POOL  AREA,  OKLAHOMA 

(After  Smith) 
Carboniferous  system : 

Pennsylvanian  series:  Feet 
Limestone,  bluish  gray;  locally  known  as  the  Lost  City  lime- 
stone   1-40 

Shale  and  sandstone 350 

Limestone,  bluish,  hard;  Checkerboard  lime  of  the  drillers. ...  21A 

Shale,  with  variable  beds  of  sandstone 215 

Coal,  Dawson 1^-2  H 

Shale,  with  irregular  beds  of  sandstone 210-350 

Limestone,  massive,  gray;  Big  lime  of  drillers 0-40 

Shale,  with  irregular  beds  of  sandstone 200  =*= 

Limestone,  Fort  Scott;  Oswego  lime  of  drillers;  bluish-gray 

limestone  with  3  to  5  feet  of  shale  near  middle 10-30 

Shale,  sandstone,  limestone,  and  coal;  Cherokee  formation..  .  .  1,000=*= 

Unconformity. 

Blue  to  white  limestone,  with  some  shale  and  thin  sandstone; 

Morrow  formation 100-120 

Unconformity. 

Mississippian  series: 

Limestone,  blue  and  brown,  locally  sandy  and  shaly ;  Pitkin ....  60  =»= 

Black  shale  with  thin  beds  of  limestone  and  sandstone;  Fayette- 

ville  formation 20-60 

Unconformity. 

Limestone,  Boone;  flinty  limestone  and  flint •       200=*= 

The  strata  between  the  top  of  the  Morrow  and  the  top  of  the 
Boone  merge  into  one  formation  in  the  southeast  corner  of  Kansas, 
thus  eliminating  the  Fayetteville,  the  Pitkin,  and  possibly  the 
Morrow  from  the  section,  so  that  the  Cherokee  rests  on  the  eroded 


294 


GEOLOGY  OF  PETROLEUM 


surface  of  the  Boone.  The  same  conditions  exist  along  the  ninety- 
sixth  meridian,  where  well  logs  do  not  show  these  three  formations 
more  than  a  few  miles  north  of  the  latitude  of  Tulsa.  Southward 
from  Tulsa  the  limestone  beds  in  the  Morrow  and  Pitkin  probably 
become  thicker  and  are  likely  to  be  mistaken  for  the  Boone  lime- 
stone. Sandstone  beds  occur  at  the  top  of  the  Morrow  and  the 


FIG.  125. — Structural  map  of  Glenn  oil  and  gas  pool  near  Tulsa,  Oklahoma. 
(After  Smith.)  The  beds  dip  west.  The  structural  contours  show  position  of 
the  surface  of  the  Fort  Scott  or  Oswego  limestone,  with  reference  to  sea  level. 
For  section  along  AB  see  Fig.  126. 

top  of  the  Boone.  The  geologic  section  is  shown  as  Fig.  124,  and 
a  structural  map  as  Fig.  125.  A  section  across  the  field  is  shown 
as  Fig.  126. 


MID-CONTINENT  FIELDS 


295 


Bristow  Quadrangle. — The  Bristow1 
quadrangle,  in  Creek  County,  is 
bordered  by  some  of  the  most  prolific 
oil  fields  of  Oklahoma.  The  nearest 
wells  of  the  east  Gushing  field  are  only 
about  1J^  miles  west  of  the  Bristow 
quadrangle.  About  9  miles  east  of  the 
quadrangle  is  the  Glenn  pool,  and  in 
the  area  that  lies  between  the  Bristow 
quadrangle  and  the  Glenn  pool  there 
are  several  minor  fields.  Several  anti- 
clines occur  in  this  quadrangle.  The 
strata  exposed  in  the  northern  part  of 
the  quadrangle  have  an  aggregate 
thickness  of  about  950  feet.  They  con- 
sist almost  entirely  of  alternating  sand- 
stone and  shale,  the  only  exceptions 
being  a  few  limestone  beds  in  the 
eastern  part  of  the  area. 

Nowata  County  Pools. — Nowata 
County  is  in  the  northeastern  part  of 
Oklahoma,  bordering  on  Kansas.  It 
contains  all  or  parts  of  the  following 
pools,  many  of  which  have  been 
heavily  productive:  Adair,  California 
Creek,  Goody's  Bluff-Alluwe-Chelsea, 
Nowata  (Claggett),  Delaware-Chil- 
ders,  and  South  Coffeeville. 

The  surface  of  the  county  is  in  gen- 
eral a  plain  in  which  the  streams  have 
eroded  wide  valleys.  It  ranges  in  ele- 
vation from  600  to  926  feet.  The  sur- 
face rocks  are  Pennsylvanian  shales, 
sandstones,  and  limestones.2 

XFATH,  A.  E. :  Structure  of  the  Northern 
Part  of  the  Bristow  Quadrangle,  Creek 
County,  Oklahoma,  with  Reference  to 
Petroleum  and  Natural  Gas.  U.  S.  Geol. 
Survey  Bull.  661,  pp.  69-99,  1918. 

2Oklahoma  Geol.  Survey  Bull.  19,  part  2, 
p.  345,  1917. 


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296 


GEOLOGY  OF  PETROLEUM 


The  structure  of  Nowata  County  is  in  general  that  of  a  west- 
ward-dipping monocline  upon  which  gentle  crumpling  is  superim- 
posed. In  some  places  the  normal  dip  is  interrupted  by  a  flatten- 
ing or  reverse  dip  to  the  east.  An  example  of  anticlinal  folding 
is  the  Goody's  Bluff-Alluwe-Chelsea  field.1  Some  other  fields  are 
not  clearly  related  to  well-defined  structural  elevations. 

Washington  County  Pools. — Washington  County  is  west  of 
Nowata  County,  in  northern  Oklahoma.  It  lies  entirely  in  the 
region  of  Pennsylvanian  rocks  and  contains  the  Dewey-Bartles- 
ville,  Canary,  Copan,  Wann,  Hogshooter,  and  Vera  pools. 


lityproducHonper  well^frrst  year 
p  g  «  S  £  £  £  S 

20  weh 
\ 

s. 

5  S  i 

'rwelljfirst"  year 

\ 

23  wet/ 

s 

0/eni 

67we/l 

?  pool,  Ok  lot 

1 

11 

\ 

/ 

" 

&7w<?//. 

\ 

O  ro  -P»  C 
0  0  £ 

Average  dcnly  production  p< 

32 

-1 
J 

\ 

£9»/eilc. 

57we//5 

~~ 

/ 

k 

si 

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27wells 

/7w<?//& 

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p" 

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- 

n 

^s 

^ 

~—  •  — 

| 

/ 

1903    1904    1905     1906     1907     1908     1909    1910 

Year 


1911      I9fe      1913      1914      1915     1916 


FIG.  127.  —  Curves  showing  yearly  decrease  in  the  first  year's  daily  produc- 
tion (in  barrels)  of  wells  on  several  properties  in  the  Glenn  pool,  Oklahoma, 
and  (below)  in  the  Bartlesville  field,  Oklahoma.  The  numbers  show  the  num- 
ber of  wells  in  each  group  used  to  supply  the  data.  (After  Beat.} 

Some  of  the  wells  drilled  during  its  early  period  of  development 
(1904-1906)  had  an  initial  production  of  1,000  barrels  a  day.  In 
1906  the  average  initial  production  per  well  was  about  73.2  barrels. 
The  average  gradually  decreased  from  that  time,  and  in  1914  it 
was  only  10.4  barrels.  At  the  end  of  1914  there  were  4,816  pro- 
ducing oil  wells  in  this  county. 

The  Dewey-Bartlesville  field  extends  westward  for  several  miles 

ildem,  p.  347. 


100- 


eoo- 


800- 


«00- 


700- 


MID-CONTINENT  FIELDS 

Micaceous  5andsto«e,5r 

-LimesW.a' 


297 


_.,ale,IO' 

-imestone,? 


Limestone,  a' 

Shale,  26' 

Sandstone.  A.7'i 

Shale,3l* 

Sandstone.B^'* 

Limeslone,2' 

Shale  and  limestone,  27* 

Stonebreaker  limestone.6* 
Shale, 12' 

Sandstone,  2'to  10'.- 
Shale,  7'tol7' 
Limestone,  2' 

Shale  and  limestone  lentils 

30'to34' 

Cryptozoon-bearing  limestone 


Jmestone.Z'toS.' 
Shale,  23' 
~Yellowlimestone,2' 
*- UNCONFORMITY 

Sandstone,  limestone^nd  shafa 

Shale,  I5'± 

Limestone  in  two  beds,  Jf 


Limestone,"red  lime','  g'toS* 
Shale  and  thin  limestone,  15'tolS' 
Gray  limestone,  5'to  10' 
Shale  and  thin  limestone, 15'toSO' 
Limestone,  5'to  10' 

Shale  and-thin  limestone,  as'to30' 
Limestone,  2' 

hale.5' 
"Limestone, 2 
Shale, 15'     . 
"Limestone,  I 
vShale,lO' 

npton  limestone  member 
r     6' to  14' 
Shale  and  thin  sandstone,20'to35' 


Sandstone,  some  limestone 

lentils,ancJshale,lZ5tol34' 

fEIgn  sandstone) 


Um.eitone.Z  toi5'(0read  limestontt 


Shale  and  sand9ton«.50'to6Z' 


Limestone,  2' 
Sandstone 


FIG.  128.— Generalized  strategraphic 
section  showing  rocks  exposed  in  north- 
western part  of  Pawhuska  quadrangle, 
Oklahoma.  (After  Heald.) 


into  Osage  County.  The  Co- 
pan  pool,  about  7  miles  north 
of  Dewey,  is  practically  con- 
tinuous with  this  field,  as  are 
also  the  Hogshooter  pool,  to 
the  southeast,  and  the  Avant- 
Ochelata  pool,  to  the  south- 
west. The  oil  is  found  in 
Cherokee  sands.  The  produc- 
ing area  seems  in  general  to  be 
closely  associated  with  very 
gentle  anticlinal  folding,  but 
the  folds  are  low  and  generally 
lack  sharp  definition.  The  pro- 
duction of  wells  in  this  field 
is  indicated  by  Fig.  127. 

Osage  County  Pools. — Osage 
County  adjoins  Washington 
County  on  the  west.  The 
eastern  and  southern  parts  of 
the  county  have  been  drilled, 
and  a  number  of  pools  have 
been  discovered,  among  them 
the  Back  Creek,  Nelagoney, 
Wynona,  Big  Heart,  Dela- 
ware, Bird  Creek,  Flatrock, 
Hominy,  and  Cleveland  (in 
part).  Federal  restrictions 
have  checked  development  of 
a  large  area  in  this  county, 
which  is  regarded  as  probably 
the  most  favorable  for  pros- 
pecting in  Oklahoma.  The  area 
is  now  being  surveyed  (1919) 
by  the  United  States  Geologi- 
cal Survey,  and  structure  con- 
tour maps  of  the  townships  are 
issued  from  time  to  time.  Sub- 
sequently the  land  is  auctioned 
by  the  Federal  officers.  Struc- 


298  GEOLOGY  OF  PETROLEUM 

turally  the  area  is  part  of  a  monocline,  on  which  many  small 
domes,  anticlines,  and  terraces  are  developed.  There  are  many 
small  faults,  most  of  which  strike  northwest.  The  rocks  that  crop 
out  are  Pennsylvanian,  and  the  oil  and  gas  are  found  mainly  in  the 
Cherokee  beds.  In  the  Hominy  field  oil  is  said  to  be  derived  from 
the  Mississippian  limestone. 

The  Pawhuska  quadrangle1  is  in  Osage  County,  just  west  of  the 
Bartlesville  field.  The  section  is  shown  as  Fig.  128.  The  gen- 
eral structure  of  the  region  is  monoclinal.  The  rocks  dip  almost 
due  west  at  an  average  rate  of  about  35  feet  to  the  mile,-  but  the 
dip  is  not  uniform.  In  some  localities  the  rocks  dip  westward  at 
triple  the  average  rate,  and  in  others  the  westward  dip  is  very  low. 
A  number  of  small  anticlinal  folds  are  known,  some  of  which  yield 
oil  and  gas. 

Kay  County  Pools.  —  Ponca  City,  Newkirk,  and  Blackwell2  are 
in  Kay  County,  near  the  Kansas  line.  The  southwest  corner  of 
Kay  County  lies  in  the  Permian  Red  Beds;  the  rest  of  the  county 
is  occupied  by  other  Permian  rocks.  The  Pennsylvanian  series  is 
found  in  normal  development  below  the  Permian,  and  the  oil  and 
gas  are  obtained  in  sands  of  the  Cherokee  formation.  The  Ponca 
City,  Newkirk,  and  Blackwell  fields  are  on  domes  or  high  places 
on  an  anticlinal  axis.  The  oil  and  gas  occur  in  several  sands,  as 
noted  below: 

Billings,  Noble  County.  —  The  Billings  field,  in  Noble  County, 
lies  about  20  miles  southwest  of  the  Ponca  City  field.  3  The  surface 
rocks  are  Permian  shale,  sandstone,  and  limestone,  which  together 
constitute  500  to  900  feet  of  beds  above  the  Neva  limestone. 
An  anticline  that  plunges  southwest  carries  a  small  dome  on  its 
southwest  end;  on  this  dome  gas  was  encountered  in  1916.  Subse- 
quently gas  wells  were  brought  in  to  the  northeast,  high  on  the 
anticline.  This  fold  (Fig.  129)  has  approximately  the  same  strike 
as  the  fold  just  south  of  Ponca  City,  and  possibly  both  are  on  the 
same  axis. 


,  K.  C.  :  Geologic  Structure  of  the  Northwestern  Part  of  the  Paw- 
huska Quadrangle,  Oklahoma.  U.  S.  Geol.  Survey  Bull.  691,  pp.  57-100,  1918. 

2OnERN,  D.  W.,  and  GARRETT,  R  E.  :  The  Ponca  City  Oil  and  Gas  Field, 
Oklahoma.  Oklahoma  Geol.  Survey  Bull.  16,  1915.  See  also  Petroleum  and 
Natural  Gas  in  Oklahoma.  Oklahoma  Geol.  Survey  Bull.  19,  part  2,  pp. 
248-280,  1917. 

3FATH,  A.  E.  :  An  Anticlinal  Fold  Near  Billings,  Noble  County,  Oklahoma. 
U.  S.  Geol.  Survey  Bull  641,  pp.  121-138,  1916. 


MID-CONTINENT  FIELDS 


299 


R.2W. 


KAY 


LEGEND 

Outcrops  of  key  beds  used 
in  determining  structure; 
smaller d.ots  indicate 
location  inferred 

Structure  contours  represent- 
ing elevation  above  sea  level  of 
lowest  prominent  outcropping 
limestone  bed;  dashed  line  in- 
dicates location  not  certain 


pprpximate  direction  of 
Strike  and  dip 


T.23 


FIG.  129. — Sketch    showing    the    anticlinal    fold 

(After  Fath.} 


near    Billings,    Oklahoma. 


300  GEOLOGY  OF  PETROLEUM 

OIL  AND  GAS  SANDS  IN  THE  BLACKWELL  FIELD,  OKLAHOMA 


Name 

Character 

Thick- 
ness 

Average 
Depth 

Correlation 

Sand 

Gas 

Feet 

20 

Feet 

225 

Sand  

Gas. 

30 

350 

Sand 

Gas. 

20 

450 

Sand  

Gas. 

25 

555 

Blackwell 

Gas. 

20 

750 

275-ft.     sand     at 

Sand 

Gas. 

30 

940 

Ponca  City. 
470-ft.     sand     at 

Sand  

Gas. 

15 

1  ,060 

Ponca  City. 
550-ft.     sand     at 

Newkirk  

Water  and  gas. 

30 

1  ,450 

Ponca  City. 
975-ft.     sand     at 

Sand  

Gas. 

20 

1  ,740 

Ponca  City. 

Sand 

Water. 

25 

1  ,800 

Ponca  
Sand  

Gas. 
Showing  of  oil. 

20 
20 

1  ,930 
1  ,970 

1  ,550-ft.   sand   at 
Ponca  City. 

Sand 

Gas,  showing  of 

15 

2,700 

Sand 

oil. 
Water. 

50 

2,300 

Sand  

Gas,  showing  of 

90 

2,640 

Lay  ton  of  Gushing. 

Sand  
Sand   .... 

oil,  water. 
Water. 
Gas,  showing  of 

25 
30 

2,775 
3,010 

Cleveland. 

Sand   

oil. 
Gas,  showing  of 

30 

3,275 

Peru. 

Swenson  

oil,  water. 
Oil. 

25 

3,360 

Oswego  (Wheeler)  . 

Garber,  Garfield  County. — The  Garber  field  is  in  Garfield  County 
a  few  miles  southwest  of  Billings.  The  surface  rocks  are  Permian 
Red  Beds,  and  the  structure  is  domatic.  Gas  and  some  oil  were 
encountered  in  Permian  beds  and  in  the  upper  part  of  the  Penn- 
sylvanian  series  in  1916.  Deeper  drilling  has  revealed  many  pro- 
ductive sands,  containing  high-grade  oil. 

Muskogee  County  Pools. — The  Muskogee  oil  field1  (Fig.  130)  is 
aTAFF,  J.  A.,  and  SHALER,  M.  K. :  Notes  on  the  Geology  of  the  Muskogee 
Oil  Fields,  Indian  Territory.     U.  S.  Geol.  Survey  Bull.  260,  p.  441,  1905. 


MID-CONTINENT  FIELDS 


301 


situated  near  and  southwest  of  Muskogee.  Oil  was  discovered 
here  in  1894,  when  two  wells  were  drilled.  In  one  of  these  wells 
oil  was  encountered  in  sand  at  a  depth  of  665  feet.  This  sand, 


Scale 
10          ts         20         25        30  mile  3. 


AreaofMississippian  Top  of  sandstone  1200*          Faults, 
limestones  to  1500' above 


OU  wells 
Missis  sippian  limestones 

FK;.  130.— Map  of  Muskogee  oil  field,  Oklahoma.   (After  Taff  and  Shaler.) 


after  being  shattered  by  an  explosive,  yielded  12  barrels  of  oil  a 
day.  Another  sand,  encountered  at  1,100  feet,  produced  60  bar- 
rels after  shooting.  The  oil  is  of  high  grade  (42°  Be.)  It  is  found 


302 


GEOLOGY  OF  PETROLEUM 


LOG  OF  ENID  WELL,  IN  THE  NORTHWEST  CORNER  OF  SEC.  30,  T.  23  N.,  R.  6  W., 
GARFIELD  COUNTY,  OKLAHOMA" 


Thick- 
ness 

Depth 

Thick- 
ness 

Depth 

Surtace  

Feet 
48 

Feet 
48 

Red  rock  

Feet 

10 

Feet 
2,618 

Red  sand  and  shale  .  . 
Lime  shell  

782 
2 

830 
832 

Lime  
Red  rock  

25 
20 

2,640 
2,660 

Red  and  sandy  shale 
Shale      . 

168 
430 

1,000 
1  430 

Slate,  white  
Lime 

20 
5 

2,680 
2  685 

Lime  

10 

1  ,440 

Slate,  white.  . 

5 

2,690 

Shale.    . 

160 

1  600 

Lime 

60 

2  750 

Lime  shell.  .  .  . 

5 

1  ,605 

Slate,  white.. 

20 

2,770 

Slate  and  rotten  shale 
Lime  

195 

20 

1,800 
1  ,820 

Slate  cave,  black 
Slate,  white.  . 

15 
15 

2,785 
2,800 

Slate 

70 

1  890 

Lime   . 

5 

2,805 

Lime  

40 

1  ,930 

Slate,  white.  .    . 

45 

2,850 

Slate 

70 

2  000 

Lime   . 

10 

2,860 

Lime  shell  

10 

2  010 

Slate,  white  

40 

2,009 

Slate 

105 

2  115 

Lime   .  .  . 

10 

2,910 

Sand  

50 

2,165 

Slate,  white..  .  . 

35 

2,945 

Red  rock  
White  slate  

53 
40 

2,220 
2  260 

Lime  
Slate,  white  

5 

50 

2,950 
3,000 

Limestone 

8 

2  268 

Lime  shells 

10 

3,010 

Red  rock  

72 

2  ,340 

Slate  

20 

3,030 

Slate,  white  
Red  rock 

30 
40 

2,370 
2  410 

Lime  shells  
Slate 

30 
55 

3,060 
3  115 

White  slate  
Red  rock  

20 
55 

2,430 
2,485 

Lime  shells  
Slate  

1 
11 

3,116 
3,127 

Slate,  white. 

35 

2  520 

Lime   .... 

15 

3,142 

Red  rock 

30 

2  550 

Slate 

23 

3,165 

Lime 

10 

2  580 

Lime     .... 

10 

3,175 

Lime,  black  

20 

2,580 

Sand  

7 

3,182 

Slate,  white  
Lime  

10 
5 

2,590 
2,595 

Slate  
Lime  and  slate.  . 

28 
155 

3,210 
3,365 

Slate,  black  

10 

2,605 

Water  at  

3,365 

aOklahoma  Geol.  Survey  Bull.  19,  part  2,  p.  200,  1917. 


in  sandstones  that  occur  near  the  base  of  the  Pennsylvanian  series. 
The  productive  sand  is  19  feet  thick. 

Structurally  the  region  is  rather  complex,  although  the  rocks 
are  not  highly  tilted.     About  6  miles  west  of  Muskogee  and  2  miles 


MID-CONTINENT  FIELDS 


303 


east  of  Taft  gas  is  found  in  the  lower  part  of  the  Pennsylvanian, 
where  the  rocks  are  arched  to  form  a  dome.  Near  Boynton,  6 
miles  southwest  of  Taft,  oil  is  concentrated  in  a  dome. 


JB9A 


FIG.  131.  —  Curves  showing  rates  of  decline  ot  the  Okmulgee-Morris  district, 
Hamilton  switch  field  and  of  Muskogee  pool,  Oklahoma.  Inset  map  showing 
he  location  of  1,  the  Gushing  field;  2,  the  Glenn  pool;  3,  the  Hamilton  Switch 
ield;  4,  the  Okmulgee-Morris  district;  5,  the  Muskogee  pool.  (After  Beal.) 


304  GEOLOGY  OF  PETROLEUM 

Okmulgee  County  Fields. — From  Muskogee  the  rocks  dip  est- 
ward  to  Okmulgee  County,  where  several  highly  productive  pools 
are  developed.  Some  of  these  are  on  very  low  anticlines.  This 
region  has  recently  come  into  considerable  production.  Decline 
curves  for  the  Okmulgee-Morris  district  and  the  Muskogee  pool 
are  shown  in  Fig.  131. 

According  to  report  considerable  oil  has  recently  been  encoun- 
tered in  or  below  the  Mississippian  limestone  in  the  Beggs  pool. 

References  for  Oklahoma 

ADAMS,  G.  I.:  The  Carboniferous  and  Permian  Age  of  the  Red  Beds  of 
Eastern  Oklahoma  from  Stratigraphic  Evidence.  Am.  Jour.  Sri.,  4th  ser., 
vol.  12,  pp.  383-386,  1901. 

• Lithologic  Phases  of  the  Pennsylvanian  and  Permian  of  Kansas, 

Indiar  Territory,  and  Oklahoma.     Science,  new  ser.,  vol.  15,  No.  379,  pp. 
545-546,  1902. 

AURIN,  FRITZ:  Correlation  of  the  Oil  Sands  of  Oklahoma.  Oklahoma  Geol. 
Survey  Circular  7,  pp.  1-16,  chart,  1917. 

Geology  of  the  Red  Beds  of  Oklahoma.     Oklahoma  Geol.  Sur- 
vey Bull.  30,  pp.  1-66,  1917. 

BEEDE,  J.  W. :  The  Bearing  of  the  Stratigraphic  History  and  Invertebrate 
Fossils  on  the  Age  of  the  Anthracolithic  Rocks  of  Kansas  and  Oklahoma. 
Jour.  Geology,  vol.  17,  pp.  710-729,  1909. 

Origin  of  the  Sediments  and  Coloring  Matter  of  the  Red  Beds  of 

Oklahoma.     Science,  new  ser.,  vol.  35,  No.  896,  pp.  348-350,  1912. 

BEAL,  C.  H. :  Geologic  Structure  in  the  Gushing  Oil  and  Gas  Field,  Okla- 
homa, and  Its  Relation  to  Oil,  Gas,  and  Water.  U.  S.  Geol.  Survey  Bull.  658, 
pp.  1-64,  1917. 

BUTTRAM,  FRANK:  The  Gushing  Oil  and  Gas  Field,  Oklahoma.  Oklahoma 
Geol.  Survey  Bull.  18,  pp.  1-64,  1914. 

FATH,  A.  E. :  Structure  of  the  Northern  Part  of  the  Bristow  Quadrangle, 
Creek  County,  Oklahoma,  with  Reference  to  Petroleum  and  Natural  Gas. 
U.  S.  Geol.  Survey  Bull.  661,  pp.  69-99,  1918. 

GARDNER,  J.  H. :  Oil  Pools  of  Southern  Oklahoma  and  Northern  Texas. 
Econ.  Geology,  vol.  10,  pp.  422-434,  1915;  Geol.  Soc.  America  Bull.,  vol.  26, 
p.  102,  1915. 

The  Mid-Continent  Oil  Fields.     Geol.  Soc.  America  Bull,  vol. 
28,  pp.  685-720,  1917. 

GOULD,  C.  N.:  Stratigraphy  of  the  McCann-  Sandstone.  Kansas  Univ. 
Quart ,  pp  175-177,  1900 

Notes  on  the  Geology  of  Parts  of  the  Seminole,  Creek,  Cherokee, 

and  Osage  Nations.     Am.  Jour.  Sci.,  4th  ser  ,  vol.  11,  pp.  185-190,  1901. 

On  the  Southern  Extension  of  the  Marion  and  Wellington  Forma- 
tions.    Kansas  Acad.  Sci.  Trans.,  vol.  17,  pp.  179-181,  1901. 

Geology  and  Water  Resources  of  Oklahoma.     U.  S.  Geol.  Survey 

Water-Supply  Paper  148,  1905. 


MID-CONTINENT  FIELDS  305 

GARDNER,  J.  H. :  Petroleum  and  Natural  Gas  in  Oklahoma.  Econ.  Geology, 
vol.  7,  pp.  719-731,  1912. 

Petroleum  in  the  Red  Beds.     Econ.  Geology,  vol.  8,  pp.  768-780, 
1913. 

The  Occurrence  of  Asphalt  in  the  State  of  Oklahoma.     Royal 

Soc.  Arts  Jour.,  vol.  63,  pp.  132-134,  1915. 

HAGER,  DORSE Y:  Gas  Pressures  and  Water  Pressures  in  Oklahoma.  Fuel 
Oil  Jour.,  vol.  6,  p.  64,  April,  1915. 

Geological  Features  of  the  Oklahoma  Oil  Fields.     Western  Eng., 

vol.  6,  pp.  13-14,  1915. 

HUTCH INSON,  L.  L. :  Rock  Asphalt,  Asphaltite,  Petroleum,  and  Natural  Gas 
in  Oklahoma.  Oklahoma  Geol.  Survey  Bull.  2,  pp.  1-256,  1911. 

JOHNSON,  R.  H.,  and  HUNTLEY,  L.  G.:  The  Equilibrium  Theory  of  Gas 
Pressures,  a  Reply  to  HAGER.  Fvel  Cil  Jour.,  vol.  6,  p.  75,  May,  1915. 

KIRK,  C.  T. :  A  Preliminary  Report  on  the  Contact  of  the  Permian  with  the 
Pennsylvanian  in  Oklahoma.  Oklahoma  Geol.  Survey  Third  Bienn.  Rept. 
for  1903,  pp.  5-14. 

MUNN,  M.  J. :  Reconnaissance  of  the  Grandfield  District,  Oklahoma.  U.  S. 
Geol.  Survey  Bull.  547,  pp.  1-85,  1914. 

OHERN,  D.  W. :  Stratigraphy  of  the  Older  Pennsylvanian  Rocks  of  North- 
eastern Oklahoma.  Oklahoma  Univ.  Research  Bull.  4. 

and  GARRETT,  R.  E. :  The  Ponca  City  Oil  and  Gas  Field.     Okla- 
homa Geol.  Survey  Bull.  16,  1915. 

POWERS,  SIDNEY  :  Age  of  the  Oil  in  Southern  Oklahoma  Fields.  Am.  Inst. 
Min.  Eng.  Bull.  113,  p.  1982,  November,  1917. 

The  Healdton  Oil  Field,  Oklahoma.     Econ.  Geology,  vol.  12, 
pp.  594-606,  1917. 

SHANNON,  C.  W.,  and  others :  Petroleum  and  Natural  Gas.  Oklahoma  Geol. 
Survey  Bull  19,  part  2,  pp.  1-536,  1917. 

SHANNON,  C.  -W.,  and  TROUT,  L.  E.:  Petroleum  and  Natural  Gas  in  Okla- 
homa. Oklahoma  Geol.  Survey  Bull  19,  part  1,  pp.  1-133,  1915. 

SMITH,  C.  D  :  Structure  of  the  Fort  Smith-Poteau  Gas  Field,  Arkansas  and 
Oklahoma.  U.  S.  Geol.  Survey  Bull  541,  pp.  23-33,  1914. 

The  Glenn  Oil  and  Gas  Pool  and  Vicinity,  Oklahoma.     U.  S. 
Geol.  Survey  Bull  541,  pp.  34-48,  1914. 

SNIDER,  L.  C  :  Geology  of  a  Portion  of  Northeastern  Oklahoma.  Oklahoma 
Geol.  Survey  Butt.  24,  part  1,  pp.  1-122,  1915. 

TAFF,  J  A  :  U  S.  Geol.  Survey  Geol  Atlas,  Coalgate  folio  (No.  74),  1901. 

—    U.  S.  Geol.  Survey  Geol  Atlas,  Tishomingo  folio  (No.  98),  1903. 

Grahamite  Deposits  in  Southeastern  Oklahoma.     U.  S.  Geol. 

Survey  Bull  380,  p.  286,  1909. 

TAFF,  J.  A.,  and  SHALER,  M.  K:  Notes  on  the  Geology  of  the  Muskogee  Oil 
Field.  U.  S.  Geol.  Survey  Bull  260,  pp.  441-445,  1905. 

TROUT,  L.  E.,  and  MYERS,  G  H.:  Bibliography  of  Oklahoma  Geology. 
Oklahoma  Geol.  Survey  Bull  25,  pp.  1-105,  1915. 

WALLIS,  B.  F. :  The  Geology  and  Economic  Value  of  the  Wapanucka  Lime- 
stone of  Oklahoma,  with  Notes  on  the  Economic  Value  of  Adjacent  Forma- 
tions. Oklahoma  Geol,  Survey  Bull  23,  pp.  1-102,  1915. 


306  GEOLOGY  OF  PETROLEUM 

WEGEMANN,  C.  H.  :  The  Duncan  Gas  Field,  Stephens  County,  Oklahoma. 
U.  S.  Geol.  Survey  Bull.  621,  pp.  43-50,  1915. 

-  Anticlinal  Structure  in  Parts  of  Cotton  and  Jefferson  Counties, 
Oklahoma.     U.  S.  Geol.  Survey  Bull.  602,  1915. 

-  The  Loco  Gas  Field,  Stephens  and  Jefferson  Counties,  Okla- 
homa.    U.  S.  Geol  Survey  Bull  621,  pp.  31-42,  1915. 

WEGEMANN,  C.  H.,  and  HEALD,  K.  C.:  The  Healdton  Oil  Field,  Carter 
County,  Oklahoma.  U.  S.  Geol.  Survey  Bull.  621,  pp.  13-30,  1915.  w 

WEGEMANN,  C.  H.,  and  HOWELL,  R.  W.:  The  Lawton  Oil  and  Gas  Field, 
Oklahoma.  U.  S.  Geol.  Survey  Bull.  621,  pp.  71-85,  1915. 

ARKANSAS 

The  Fort  Smith-Poteau  gas  field1  is  south  of  Fort  Smith,  in 
Arkansas  and  Oklahoma.  Natural  gas  was  discovered  some  years 
ago  in  Massard  Prairie,  5  miles  southeast  of  Fort  Smith,  and  also 
about  2  miles  southeast  of  Mansfield,  Arkansas,  and  more  recently 
it  has  been  found  3  miles  east  of  Poteau,  Oklahoma. 

The  rocks  are  Pennsylvanian.  2  The  oldest  formation  in  the 
region  described  by  Smith  is  the  Atoka,  a  series  of  alternating 
shales  and  sandstones  6,000  to  7,000  feet  thick.  The  sandstone 
constitutes  but  a  small  part  of  the  formation  and  lies  in  zones  about 
100  feet  thick,  separated  by  beds  of  shale  1,000  to  1,200  feet  thick. 
In  some  areas  the  formation  consists  almost  entirely  of  shale;  in 
others  the  beds  of  sandstone  are  thick  and  massive.  Above  the 
Atoka  is  the  Hartshorn  sandstone,  from  100  to  200  feet  thick,  fol- 
lowed by  the  McAlester  shale,  from  2,000  to  2,500  feet  thick.  The 
Savanna  formation,  which  overlies  the  McAlester,  consists  of  three 
prominent  zones  of  sandstone,  each  ranging  in  thickness  between 
100  and  200  feet,  separated  by  masses  of  shale.  Its  total  thickness 
is  estimated  at  1,200  to  1,500  feet.  Above  the  Savanna  is  the 
Boggy  shale,  about  2,300  feet  thick,  which  contains  also  about 
400  feet  of  sandstone. 

The  country  lies  between  the  complexly  folded  and  faulted 
Ouachita  Mountains,  to  the  south,  and  the  gently  tilted  Boston 
Mountains,  to  the  north.  The  rocks  are  thrown  into  rather  steep 


,  C.  D.  :  Structure  of  the  Fort  Smith-Poteau  Gas  Field,  Arkansas  and 
Oklahoma.  U.  S.  Geol.  Survey  Bull  541,  p.  23,  1914. 

COLLIER,  A.  J.  :  The  Arkansas  Coal  Field.  U.  S.  Geol.  Survey  Bull.  326, 
1907. 

TAFF,  J.  A.,  and  ADAMS,  G.  I.  :  Geology  of  the  Eastern  Choctaw  Coal  Field, 
Indian  Territory.  U.  S.  Geol.  Survey  Twenty-first  Ann.  Rept.,  part  2,  pp. 
257-311,  1900. 


MID-CONTINENT  FIELDS  307 

folds,  anticlines  alternating  with  synclines.     There  are  also  strike 
faults. 

Three  areas  in  this  region  yield  gas.  Each  is  at  the  crest  of  an 
anticline.  The  principal  reservoirs  are  the  Hartshorn  sandstone 
and  the  sands  in  the  Atoka  formation. 

KANSAS 

In  Kansas,  which  contains  the  northern  part  of  the  Mid-Con- 
tinent field,  the  geologic  conditions  are  essentially  similar  to  those 
in  Oklahoma,  already  described.  The  rocks  that  crop  out  in 
Kansas1  are  all  sedimentary  beds.  The  oldest  rocks  are  Missis- 
sippian  strata,  which  are  exposed  only  in  the  southeast  corner  of 
the  State.  To  the  west  and  north  is  a  broad  area  of  Pennsylvanian 
strata  that  extends  to  the  north  boundary.  West  of  that  is  a  belt 
of  Permian  beds,  narrow  at  the  Nebraska  line  and  very  broad  at 
the  Oklahoma  line.  West  of  the  Permian  belt  is  a  broad  area  of 
Mesozoic  and  Cenozoic  beds  that  extends  to  the  west  border  of 
the  State. 

The  oil  and  gas  are  found  mainly  in  the  Cherokee  formation, 
which  is  the  principal  producing  formation  in  northern  Oklahoma, 
and  the  fields  exhibit  similar  structural  features.  In  Kansas  the 
production  of  gas  is  relatively  important.  The  Kansas  fields  are 
near  great  industrial  centers.  The  readily  accessible  market  of 
Kansas  City,  Missouri,  and  the  development  of  zinc-smelting, 
clay-burning,  and  glass  and  cement  manufacturing  plants  in  Kan- 
sas have  greatly  stimulated  gas  exploration  in  these  fields. 

The  strata  of  Kansas  dip  northwest,  away  from  the  Ozark  up- 
life,  in  general  at  the  rate  of  30  feet  to  the  mile  or  less.  The  deposits 
are  on  ^the  great  westward-dipping  monocline,  and  the  minor 
structural  features  that  localize  the  accumulations  are  mainly 
anticlines,  domes,  flutings  on  monoclines,  or  structural  terraces. 

^AWORTH,  ERASMUS,  and  others :  Special  Report  on  Oil  and  Gas.  Kansas 
Geol.  Survey,  vol.  9,  pp.  1-586,  1908. 

SCHRADER,  F.  C.,  and  HA  WORTH,  ERASMUS:  Economic  Geology  of  the  Inde- 
pendence Quadrangle,  Kansas.  U.  S.  Geol.  Survey  Bull  296,  pp.  1-74,  1906. 

ADAMS,  G.  I.,  HAWORTH,  ERASMUS,  and  CRANE,  W.  R.:  Economic  Geology 
of  the  lola  quadrangle,  Kansas.  U.  S.  Geol.  Survey  Bull.  238,  pp.  1-83,  1904. 

ORTON,  EDWARD:  Geological  Structure  of  the  lola  Gas  Field.  Geol.  Soc. 
America  Bull,  vol.  10,  pp.  99-106,  1899. 

ADAMS,  G.  I. :  Oil  and  Gas  Fields  of  the  Western  Interior  and  Northern 
Texas  Coal  Measures  and  of  the  Upper  Cretaceous  and  Tertiary  of  the  Western 
Gulf  Coast,  U.  S.  Geol.  Survey  Bull.  184,  pp.  1-64,  1901. 


308 


GEOLOGY  OF  PETROLEUM 


In  Kansas  granite  occurs  at  relatively  shallow  depths  on  some 
of  the  domes.1  At  Elmdale,  Onaga,  Wabaunsee,  and  Zeandale 
granite  is  encountered  at  stratigraphic  horizons  as  high  as  1,000 


FIG.  132. — Diagram  showing  limestones  thinning  out  southwestward  from 
Kansas  to  Oklahoma.    (After  Schrader  and  Haworth.} 

feet  above  the  base  of  the  Pennsylvanian  series.     At  most  places 
there  is  no  evidence  of  metamorphic  action  in  the  beds  immediately 

BAYLOR,  C.  H. :  The  Granites  of  Kansas.     Southwestern  Assoc.  Petrol. 
Geologists  Bull.,  vol.  1,  pp.  111-126,  1917. 


MID-CONTINENT  FIELDS  309 

overlying  the  granite.  It  is  believed  that  the  granite  represents 
old  knobs  or  probably  ridges,  that  were  submerged  in  the  Pennsyl- 
vanian  sea  and  ultimately  covered  by  sedimentary  material.  At 
a  later  period  these  points,  which  were  lines  of  weakness,  became 
loci  of  movement  so  that  the  strata  above  them  were  folded.  The 
dome  at  Elmdale,  according  to  Gardner,1  shows  a  reverse  dip  of 
nearly  300  feet  at  angles  as  steep  as  5°.  The  depth  from  the  present 
surface  to  the  top  of  the  granite  ranges  from  950  feet  on  the  fold 
at  Zeandale  to  2,500  feet  on  the  dome  near  Cotton  wood  Falls  or 
Elmdale. 

In  Kansas  the  Pennsylvanian  contains  more  limestone  than  in 
Oklahoma.  The  limestones,  as  shown  by  Fig.  132,  thin  out 
toward  the  Oklahoma  boundary. 

GENERAL  STRATIGRAPHIC  SECTION  IN  THE  OIL  AND  GAS  REGION  OF  KANSAS 
(After  Haworth,  Adams,  Schrader,  Gardner,  and  Others) 

Permian  series: 

1.  Red  and  gray  sandstones  with  beds  of  red  and  vari-colored  Feet 

shale.     Includes  salt  and  gypsum  in  upper  portion 1,000-1,500 

2.  Wellington  shale 75-150 

3.  Marion  limestone 100-200 

4.  Winfield  formation;  limestone  and  shale 20-30 

5.  Doyle  shale 50-70 

6.  Fort  Riley  limestone;  crops  out  at  Augusta 40-50 

7.  Florence  flint 15-25 

8.  Matfield  shale 60-70 

9.  Wreford  limestone  (base  of  Permian,  according  to  Prosser 

and  to  Adams) 35-55 

10.  Neosho  formation  and  Florence  shale  or  Garrison  formation  140-150 

11.  Cottonwood  limestone 5-10 

12.  Eskridge  shale '.  30-40 

13.  Neva  limestone 5-15 

14.  Elmdale  formation;  shale  and  limestone  (base  of  Permian, 

according  to  Beede) 120-140 

Pennsylvanian  series: 

1.  Americus  limestone 6-10 

2.  Admire  shale;  probably  includes  oil  sand  at  a  depth  of  about 

650  feet  at  Eldorado 275-325 

3.  fimporia  limestone. 5-10 

4.  Willard  shale 60-190 

^GARDNER,  J.  H. :  The  Mid-Continent  Oil  Fields.     Geol.  Soc.  America  Bull, 

vol.  28,  p.  690,  1917. 
Op.  cit.,  p.  691. 


310 


GEOLOGY  OF  PETROLEUM 


Feet 


5.  Burlingame  limestone 

6.  Scranton  shale 

7.  Howard  limestone 

8.  Severy  shale 

9.  Topeka  limestone 

10.  Calhoun  shale 

11.  Deer  Creek  limestone 

12.  Tecumseh  shale 

13.  Lecompton  limestone 

14.  Kanawa  shale 

15.  Oread  limestone 

16.  Lawrence  shale;  includes  Chautauqua  sandstone  member, 

which  is  the  most  persistent  bed  of  sandstone  in  this  por- 
tion of  section.  Probably  to  be  correlated  with  the  sur- 
face bed  at  Toronto.  Occurs  at  1,550  feet  in  wells  at 
Augusta  and  Eldorado 

17.  Kickapoo  limestone 

18.  Le  Roy  shale 

19.  Stanton  limestone 

20.  Vilas  shale 

21.  Allen  limestone 

22    Lane  shale 

23.  lola  limestone 

24.  Chanute  shale 

25.  Drum  limestone 

26.  Cherry  vale  shale.     About  the'horizon  of  the  oil  sand  occurr- 

ing at  2,450  feet  at  Augusta  and  Eldorado  (Gardner) .  .  . 

27.  Dennis  limestone,  Galesburg  shale,  and  Mound  Valley 

limestone 

28.  Ladore  shale , 

29.  Bethany  Falls  limestone 

30.  Pleasanton  shale 

31.  Coffeeville  limestone 

32.  Walnut  shale 

33.  Altamont  limestone 

34.  Bandera  shale 

35.  Pawnee  limestone.     Horizon  of  Peru  oil  sand 

36.  Labette  shale 

37.  Fort  Scott  (Oswego)  limestone 

38.  Cherokee  shale.     Includes  main  oil  sands  of  Kansas  out- 

side of  Augusta  and  Eldorado  regions.  Contains  Bar- 
tlesville  and  Burgess  sands 

Mississippian  series: 

Limestone,  calcareous  shale  and  chert  shown  in  Neosho  well. 
Boone  formation.  . 


MID-CONTINENT  FIELDS 


311 


Probably  older  than  Mississippian: 

1.  Dolomitic  limestone,  sandstone,  and  chert  in  Neosho  well.. 

3.  Conglomerate  and  shale  in  Neosho  well 

4.  Sandstone,  conglomeratic  with  pebbles  up  to  three-quarters 

inch  in  diameter;  shown  in  Neosho  well 


L.U 


o 

7 

ro 

co 

rH 

C5 

& 


Feet 
77 

23 
1,823 


The  structural  features  are  in  general  similar  to  those  of  the 
Oklahoma  fields.  The  principal  fields  are  shown  in  Fig.  133, 
and  sections  are  given  in  Fig  134. 


312 


GEOLOGY  OF  PETROLEUM 


In  the  Peru  region,  lying  mainly  in  Chautauqua  County,  but 
extending  eastward  into  the  western  part  of  Montgomery  County, 


0«thin 

fW 
o-i 


1,400 


1,800 


2,600 


2,800 


jandsaa.l 

rs'tone,20' 
Shale,  60' 

stone,  20' 

^m,,»22S- 
Shale,  100' 

Shale,  88' 


Sandstone.EO' 
Shale,78' 
Oil  sand.  13' 

sO3  Shale.  16*' 

Gas  sand,  10* 
Sh.le,ZlOf 


Limestone.  Z62' 

[  Black  bituminoua  shate.35' 

Li  mestone.  Z07* 
Sandstone.U' 

Lime  stone.  375* 

Sandstone,  Zt' 
L.mestone.  Z8Z' 

Sar.d3tone.4S' 


Surface  soil  and  clay.  31' 
Sandstone,  slightly  calcsreou«,34 
Shale,  gray,  calcareous,  •«' 

i 


Li  mestone,  58' 
Sandstone,  67' 

Limestone.  21' 
Shale,  J7' 

Lime»tone.with  shale,  16 
Black  ahaic,  29' 

Limestone,  arenaceous.TS* 

Shalt.  105' 

limestone,  with  bluish  shale,  47* 

ISl^l'fmist^TS!""-*' 
Shale,  slightly  calcareous,  33* 
Limestone,  with  some  shale.  25' 

Shale,  dark,  calcareous,  IS}' 

le,  bluish.fHghtly  calcareous,}' 


Surf»ce  soil,  19' 


n. 

•  Limestone,  magne»ien,aren»ceo'JS,  8 
Sandstone,  39' 

Limestone  and  sandstone,  M-* 
Limestone,  90' 

•  Sandstone,  7' 
Limestone.  6" 
Sandstone.  67' 
Limestone,  15' 
Sandstone,  66* 

Limestone,  121' 

Sandstone,  8' 
Limestone,  35' 


Sandstone.  Z30' 


l.mestooe.3 

Cherryvjle  shale», 
Dennis  I.  mestone,  24' 
Calesburg  shales,  25 

Mound  Valley  limestone,  58' 
Ladore  shales,  ?3' 
Bethany  limestone,  23* 
Pleasanton  shales,  60' 


Walnut  shales,  133' 

Altamont  lime,  16* 
Bandera  shales.  54' 
Pawnee  limestone,  24-' 
Labette  shale,  26' 
Fort  Scott  limestone  4fi' 


Cherokee  shale,.  366' 


Mississippi  limestone,  168' 

Limestone,  arenaceous,24' 
Shale,  calcareous,3l' 
Limestone,50' 
.Shale,  calcareous,  17 
•Limestone.  5 


Sandstone.dolomitic,  23' 


Dolomite,  arenaceous,  326' 


Sand,  52' 
Conglomerate,  Z3* 


A  sandstone  conglomerate 
varying  slightly  in  color 
and  carbonate  content, 
and  in  size  of  fr 


FIG.  134.— Records  of  deep  wells  at  Caney,  Neodesha  and  Tola,  southeastern 
Kansas.   (After  Heald.) 


MID-CONTINENT  FIELDS 


313 


oil  is  accumulated  on  a  great  structural  terrace  where  the  beds  He 
practically  flat.  For  25  miles  down  the  dip  the  rocks  dip  4  feet 
to  the  mile.  West  of  this  terrace  for  25  miles  the  dip  is  about  50 


T.28S 


Shale  SO-     135 

Lime  i3.5-    no 

5Mal«  170-     1 0O 

Rcatrock  190-    204 

.Shale  203-    ZOO 

L/me  240-    26o 

3hole  250-    3jo 

Lim«  330-    3«o 

Shate  360-   415 

Sand  415-   430 

5ho/«  430-    340 

Sand  &40-    460 

Shale  &iO-    6tO 


if: 

Shale 


&g  IIS:  S 

Uimv         9  JO-    9 
Shale       940-    9 


:  III 


70 

970- I02S 
029- I O4O 
040- IOSO 
I OjO- IO75 


Lime     1073-1333 


Shale    1333-  I40O 


Shale     IS03-IAZ6 
Sand    I52S-I333 


Shale     1333-  I7iO 


Lima      1710-1060 


L,m»    t   Oi-tl90 


LirrM  23IO-Z370 
5  hole  21 70 -24  50 

i.i'm<  243O-Z46O 
Sand  24to-2490 
Auqvtto  Oil  Sand 


R.se 


FIG.(  135. — Map  and  section  of  Augusta  and  Eldorado  fields,  Butler  County, 
Kansas.  Contours   are   based   on   outcrop   of   Fort   Riley   limestone.   (After 
Hager,  Bales  and  Walker.) 


314  GEOLOGY  OF  PETROLEUM 

feet  to  the  mile,  and  east  of  it  for  25  miles  it  is  about  30  feet  to 
the  mile. 

In  the  Independence  quadrangle,  Montgomery  County,  which 
lies  just  east  of  the  Peru  pool,  between  Independence  and  Coffey- 
ville,  there  is  an  extensive  area  yielding  oil  and  gas  which  is  situated 
on  the  crest  and  well  down  the  flanks  of  a  gentle  anticlinal  fold. 
In  Wilson  County  (Fredonia  pool)  and  in  Woodson  County,  to  the 
north,  gas  and  some  oil  are  found  on  subordinate  folds  that  rise  not 
more  than  50  feet  above  the  general  plane  of  the  monocline.  In 
the  lola  quadrangle,  Allen  and  Neosho  Counties,  accumulations 
occur  on  the  monocline  in  gentle  structural  ravines  and  terraces 
with  axes  that  strike  approximately  with  the  beds.  In  the  lola 
and  La  Harpe  field,  in  northern  Allen  County,  there  is  a  low  anti- 
cline or  terrace  about  8  miles  wide. 

The  Paola  field,  in  Miami  and  Franklin  Counties,  is  on  a  terrace 
where  for  40  miles  down  the  dip  of  the  monocline  the  beds  dip  5 
feet  to  the  mile.  West  of  this  area  in  Osage  County,  the  dip  is 
about  20  feet  to  the  mile. 

In  the  Eldorado  and  Augusta  fields,  Butler  County  (Fig.  135), 
the  oil  and  gas  have  accumulated  in  well-defined  domes  that  are 
superimposed  on  the  monocline. 

Pools  have  recently  been  developed  at  Elbing,  Peabody  and 

Florence. 

MISSOURI 

Small  quantities  of  oil  and  gas  have  been  produced  near  Kansas 
City,  Missouri,  in  Cass  and  Jackson  Counties,  which  lie  on  the  west 
border  of  the  State.  The  outcropping  rocks  are  of  Pennsylvanian 
age.  These  strata  extend  to  depths  of  650  to  875  feet  or  more. 
The  series  is  divided  into  two  groups  of  rocks  classified  as  the  upper 
or  Missouri  group  and  the  lower  or  Des  Moines  group.  The 
exposed  strata  belong  chiefly  to  the  upper  group,  but  only  its 
lowest  formation,  the  Kansas  City,  is  present.  The  limestone 
members  of  this  formation  crop  out  conspicuously  over  nearly  all 
of  the  area. 

The  regional  dip  of  the  rock  beds  is  northwest,  off  the  flank  of 
the  Ozark  dome.  This  dip  is,  however,  very  low,  the  average 
across  Jackson  and  Cass  Counties  being  only  from  6  to  10  feet  in 
a  mile.1 

WILSON,  M.  E. :  Oil  and  Gas  Possibilities  in  the  Belton  Area.  Missouri 
Bur.  Geology  and  Mines,  1918. 


MID-CONTINENT  FIELDS 


315 


Series  Group 


Ibickneaa 

(in  feet) 


Character  of  Rock 


200  + 


Alternating  beds  of  limestone 
and  shale  with  a  few  non- 
persistent  beds  of  sandstone 


b 


Chiefly  alternating  shale  and 
sandstone  with  thin  uon, 
persistent  limestones 


M 


60  + 


Thin  alternating  beds  of  limestone 
Shale  and  sandstone 


1=  430  + 


Chiefly  shale  aud  sandstone,  thin 
seams  of  coal  and  limestones 


155 1 


Chiefly  limestone   with  chert 


316  GEOLOGY  OF  PETROLEUM 

In  the  region  near  Belton  and  Hickman  Mills  there  are  a  number 
of  low  anticlines,  domes,  monoclines,  terraces,  and  synclines. 
Southwest  of  Belton  there  is  a  small  area  of  complicated  faulting. 
In  several  wells  sunk  to  depths  of  about  400  feet  oil  or  gas  or  both 
have  been  encountered.  In  1909  five  wells  produced  about  300 
barrels  a  month  of  a  heavy  oil  with  paraffin  base  which  commanded 
a  good  price  for  use  as  lubricating  oil.  The  oil  was  obtained  from 
sands  near  the  bottom  of  a  shallow  syncline.  A  section  of  the 
rocks  is  shown  in  Fig.  136. 

RED  RIVER  REGION,  OKLAHOMA  AND  TEXAS 

General  Features. — The  Red  River  region  of  southern  Okla- 
homa and  northern  Texas  (Fig.  137)  includes  parts  or  all  of  Carter, 
Love,  Stephens,  Jefferson,  Cotton,  and  Comanche  Counties,  Okla- 
homa, and  Clay,  Vichita,  and  Wilbarger  Counties,  Texas.  The 


— 

\ 


w2J 
FIG.  137. — Index  map  of  Red  River  region,  Oklahoma  and  Texas. 

Red  River  oil  and  gas  pools  include  the  Healdton,  Fox,  Graham, 
Loco,  Duncan,  and  Lawton  pools  in  Oklahoma,  and  the  Electra, 
Burkburnett,  and  Petrolia  fields  of  Texas.  In  this  region,  as 
shown  by  the  contact  of  Pennsylvanian  with  Permian  rocks  (Fig. 
118,  p.  272)  there  is  an  embayment  in  the  Permian  outcrop  south  of 
the  Arbuckle  Mountains  near  the  Red  River.  In  the  region  of 
this  embayment  there  is  a  great  synclinal  trough.  The  beds  dip 
southward  from  the  Arbuckle  Mountains  and  northwestward  from 
the  Llano  uplift,  in  the  region  south  of  the  Red  River.  The  axis 
of  the  syncline  plunges  west.  Superimposed  on  the  larger  syn- 
clinal basin  and  probably  crossing  it,  is  the  great  Red  River  zone 


MID-CONTINENT  FIELDS  317 

of  deformation,1  which  here  has  been  identified,  mainly  by  drilling. 
It  extends  along  Red  River  and  through  counties  that  border  the 
river  for  over  100  miles.  This  great  uplift  is  probably  of  pre- 
Pennsylvanian  age,  according  to  Hager,  who  states  that  minor 
anticlines  and  domes  such  as  those  that  exist  at  Electra  and  Pe- 
trolia,  are  due  to  movements  of  readjustment  along  old  lines  of 
stress  in  highly  folded  Ordovician  rocks  beneath.  The  less  intense 
deformation  took  place  in  Post  Pennsylvanian  time. 

The  surface  rocks  are  of  Permian  age,  and  the  oil  and  gas  are 
produced  mainly  from  underlying  Pennsylvanian  strata,  although 
the  lower  Permian  also  supplies  gas  and  some  oil.  Possibly  some 
of  the  oil  has  come  from  strata  lower  than  the  Pennsylvanian. 

GENERAL  STRATIGRAPHIC  SECTION  SOUTH  OF  THE  ARBUCKLE  MOUNTAINS 

IN  OKLAHOMA" 

Lower  Cretaceous  (Comanche  series) :  Feet 

1.  Silo  sandstone 200 

2.  Pennington  limestone 10-15 

3.  Bokchito  formation 140 

4.  Caddo  limestone 60 

5.  Kiamichi  formation 150 

6.  Goodland  limestone 25 

7.  Trinity  sand,  which  includes  the  sand  yielding  light  oil  in 

Madill  field  and  the  gas  sand  at  Woodville 200-400 

Unconformity. 

Permian: 

Red  sandstone,  varicolored  shale,  and  beds  of  clay-iron  con- 
glomerate with  thin  lenses  of  limestone 400-1,500 

Unconformity. 

Pennsylvanian : 

1.  Franks  conglomerate.     Limestone   (Wapanucka)   at  top. 

Beds  of  chert,  gravel,  boulders,  and  sandstone;  formation 

of  local  extent  near  mountains .  500 

Unconformity. 

2.  Glenn  formation;  blue  shale  with  lenticular  beds  of  sand- 

stone.    Probable  horizon  of  the  main  oil  sand,  Healdton 

field 1,000-3,000 

Unconformity. 

JHAGER,  LEE:  Red  River  Uplift  Has  Another  Angle.  Oil  and  Gas  Jour., 
vol.  18,  pp.  64-65,  1919. 

°TAFF,  J.  A.:  U.  S.  Geol.  Survey  Geol.  Atlas,  Tishomingo  folio  (No.  98),  1903;  Some  Economic 
Notes  by  Gardner.  Geol.  Soc.  America  Bull.,  vol.  28,  p.  697,  1917. 


318  GEOLOGY  OF  PETROLEUM 

Mississippian:  Feet 

1.  Caney  shale.     Top  is  blue  shale  with  sandy  lentils  and 

lower  portion  is  black  fissile  shale  with  concretions  of 

dark-blue  fossiliferous  limestone 1,500 

2.  Sycamore  limestone 0-160 

Devonian: 
Woodford  chert 600 

Silurian: 

1.  Hunton  limestone 0-200 

2.  Sylvan  shale.     Blue  clay  shale 50-300 

Ordovician : 

1.  Viola  limestone:  white  and  bluish 750 

2.  Simpson  formation;  siliceous  sandstone,  bituminous  sand- 

stone, fossiliferous  limestone,  calcareous  sandstone  and 
shale.  Possibly  contains  deep  oil  sand  near  center  of 
Healdton  field,  according  to  Powers 1,600 

Cambro-Ordovician : 

Arbuckle  limestone;  massive  and  thin  bedded,  white  and  light 

blue  limestone  with  cherty  concretions 4,000-6,000 

Cambrian : 

Reagan  sandstone;  coarse  dark  brown  sandstone  with  cal- 
careous sandstone  and  shale  at  top 50-150 

Pre-Cambrian :  Granite. 

GENERAL  STRATIGRAPHIC  SECTION  IN  NORTHERN  TEXAS 
(After  Paige,  Hill,  and  Others,  with  Economic  Notes  by  Gardner,  Matteson, 

and  Others) 
Tertiary  (Eocene):  Feet 

1.  Cook  Mountain  and  Mount  Selman  (St.  Maurice  of  Louisi- 

ana, Claiborne).  Consists  of  clays,  clay-iron  con- 
glomerates, and  calcareous  glauconitic  beds. 

2.  Wilcox  group  (Sabine  formation).     Sands,  clays,  and  con- 

glomerates with  beds  of  lignite 400-500 

3:  Midway  group.     Chiefly  clays  with  some  limestone 200-300 

Upper  Cretaceous  (Gulf  series) : 

1.  Navarro  group.     Clay  marls  and  glauconitic  sands 400-700 

2.  Taylor  marls  group.     Beds  of  clay  and  sandy  to  calcareous 

soft  shale,  with  local  lenses  of  sandstone.  Contains 
Nacatoch  gas  sand  of  Caddo  field,  oil  sands  of  Corsicana 
field,  and  oil-bearing  igneous  rock  (tuff?)  of  Thrall  field  200-500 

3.  Austin  group  (Annona  chalk  and  Brownstown  marl).    Con- 

tains some  oil  and  gas  in  Caddo  field 200-600 


MID-CONTINENT  FIELDS 


319 


4.  Eagle  Ford  group.     Chiefly  clays  containing  the  Blossom  feet 

oil  sand  of  Caddo  field 150-400 

5.  Woodbine  sand.     Massive  soft  sandstone  with  some  shale. 

Main  oil  sand  of  Caddo  oil  field.  Occupies  approximate 
time  interval  of  Dakota  sandstone  in  New  Mexico  and 
northward  into  Canada 50-100 

Lower  Cretaceous  (Comanche  series) : 

1.  Washita  group.     Impure  limestone  with  beds  of  shale  and 

marl.  Contains  water  sand  locally  at  Paris,  Texas;  in- 
cludes, in  descending  order,  the  Pennington  limestone, 
Bokchito  formation,  Caddo  limestone,  and  Kiamichi 
formation  (Denison,  Fort  Worth,  and  Preston  forma- 
tions)    175-400 

2.  Fredericksburg  group.     Massive  white  limestone  beds,  in- 

cluding the  Goodland  limestone  (Edwards  limestone  and 

Walnut  formation) 25-200 

3.  Trinity  sand.     Contains  the  oil  of  the  South  Bosque  field 

in  top  member 200-400 

Permian : 

1.  Double   Mountain  group.     Sandstone,   limestone,   sandy 

shale,  red  and  blue  clays,  with  beds  of  gypsum  and  salt.     1,800-2,000 

2.  Clear  Fork  group.     Thin-bedded  sandstone,   magnesian 

and  carbonaceous  limestone,  red  and  blue  clay  shale  and 
irregular  beds  of  cemented  clay-iron  concretions.  Some 
gypsum 1,500-2,000 

3.  Wichita  group.     Sandstone  of  various  colors.     Red  and 

bluish  clay  shale  and  beds  of  clay-iron  concretions  or 
"Mud-lump  conglomerate."  Beds  of  limestone  rare 
east  of  Baylor  County.  Correlated  with  limestone  and 
shale  series  known  as  the  Albany  formation  in  Baylor 
County 1,250-2,000 

Pennsylvanian : 

1.  Cisco  group.     Sandstone,   limestone,   gray   sandy   shale, 

dark-gray  shale,  and  conglomerate.  Contains  coal  7. 
Includes  upper  oil  and  gas  sands  in  Petrolia  and  Electra 
fields. 800-900 

2.  Canyon  group.     Sandstone,  dark-blue  shale,  conglomerate, 

coal,  and  beds  of  massive  escarpment-forming  limestone. 
Includes  lower  oil  and  gas  sands  in  Electra  and  Petrolia 
fields 800-950 

3.  Strawn  group.     Sandstone,  clay,  carbonaceous  shale,  and 

chert  conglomerate.     Includes  Millsap  formations,  or 
beds  for  1,000  feet  below  coal  1.     Contains  oil  and  gas 
sands  in  Strawn,  Ranger,  Moran,  and  Brownwood  fields       950-3,700 
Unconformity. 


320  GEOLOGY  OF  PETROLEUM 

Mississippian  (Bend  series) :  Feet 

1.  Smith  wick    shale.     Black    shale.     Contains    sand    lenses 

that,  according  to  Matteson,  yield  oil  in  Allen  well,  east 

of  Ranger,  and  in  Black  well,  northern  Stephens  County  175-500 

2.  Marble  Falls  limestone.     Bituminous  limestone,  and  some 

shale.  Oil  and  gas  in  Ranger  and  Electra  fields  and 
deep  sands  of  Burkburnett  pools.  Contact  with  Smith- 
wich  yields  oil  in  Ranger  and  Caddo  pools 350-400 

3.  Lower  Bend  shale.     Black  shale 0-125 

Unconformity. 

Ordovician : 

1.  Ellenberger  limestone 400 

Healdton,  Oklahoma. — Healdton,  Carter  County,  Oklahoma,1 
lies  to  the  south  of  the  Arbuckle-Wichita  uplift  and  is  about  12 
miles  southwest  of  the  Arbuckle  Mountains.  Petroleum  was  dis- 
covered here  in  1913,  and  the  field  was  developed  within  three 
years  to  one  of  the  most  productive  fields  in  Oklahoma,  yielding 
daily  over  60,000  barrels.  The  rocks  at  the  surface  are  Permian 
Red  Beds  and  consist  of  red  and  gray  shale,  alternating  with 
brown,  white,  and  red  sandstone  and  thin  conglomerate  beds. 
The  beds,  according  to  Wegemann  and  Heald,  are  at  least  in  part 
of  fresh-water  origin.  From  the  surface  to  a  depth  of  600  to  950 
feet  the  strata  are  principally  shales,  with  a  few  water-bearing 
sandstones.  Below  these  beds  is  a  zone  250  feet  thick  which  con- 
tains four  or  more  petroliferous  sands  separated  by  beds  of  shale. 
In  some  wells  five  sands  contain  oil.  Most  of  the  oil  produced  in 
1915  came  from  sands  800  to  1,150  feet  deep.  The  higher  petrolif- 
erous strata  are  classified  as  Permian  by  Wegemann  and  Heald,2 
and  also  by  Aurin.3  Powers,  however,  classes  them  as  Penn- 
sylvanian.  The  deeper  oil-bearing  strata  are  Pennsylvanian. 

Structurally  the  field  is  an  anticline  on  which  several  small 
domes  are  superimposed.  The  oil  has  accumulated  at  the  top  of 

WEGEMANN,  C.  H.,  and  HEALD,  K.  C.:  The  Healdton  Oil  Field,  Carter 
County,  Oklahoma.  U.  S.  Geol.  Survey  Bull.  621,  pp.  13-30,  1915. 

POWERS,  SIDNEY  :  The  Healdton  Oil  Field,  Oklahoma.  Econ.  Geology,  vol. 
12,  pp.  594-606,  1917;  Age  of  the  Oil  in  Oklahoma  Fields.  Am.  Inst.  Min. 
Eng.  Bull  113,  p.  1982,  1917. 

SHANNON,  C.  W.,  and  others:  Petroleum  and  Natural  Gas  in  Oklahoma. 
Oklahoma  Geol.  Survey  Bull.  19,  part  2,  pp.  79-101. 

20p.  tit.,  p.  24. 

SHANNON,  C.  W.,  and  others:  Op,  cit.,  insert  table. 


MID-CONTINENT  FIELDS  321 

the  anticline,  on  the  domes,  and  in  the  small  structural  depressions 
between  them.  On  the  flanks  of  the  fold  the  beds  carry  salt  water. 
Figs.  29  and  30  (pp.  124-125)  are  a  structure  map  and  a  stereogram 
by  Wegemann  and  Heald.  Possibly  a  small  part  of  the  oil  is 
derived  from  the  Ordovician  beds,  which  are  covered  by  the 
Carboniferous  beds.  (See  Fig.  138.) 

Powers  l  states  that  an  angular  unconformity  separates  the  Ordo- 
vician from  the  Pennsylvanian  rocks,  the  former  being  tilted  at 
considerably  higher  angles.  The  deeper  sands,  which  have  proved 
highly  productive  around  the  outer  margins  of  the  field,  are  lacking 
in  its  center,  where  pre-Pennsylvanian  rocks  only  are  found  below 
the  higher  sands  (Fig.  138). 

At  Fox  and  at  Graham,  which  lie  north  of  the  Heald  ton  field, 
the  surface  rocks  are  Permian.  The  Permian  is  thicker  than  at 
Heald  ton,  and  the  oil-bearing  strata  lie  at  greater  depths.  The 
petroliferous  beds  are  at  approximately  the  same  horizons.  Anti- 
clines are  developed  at  Fox  and  at  Graham  (Fig.  138),  but  these 


Heer/efton 


FIG.  138. — Cross  section  of  the  Healdton  field,  Fox  and  Wheeler  anticlines, 
Oklahoma,  showing  the  relation  of  the  buried  Healdton  Hills  composed  of 
Ordovician  strata  to  the  overlying  Pennsylvanian  and  Permian  strata.  Length 
of  section  21  miles;  vertical  scale  four  times  horizontal  scale.  (After  Powers.) 


pools,  which  lie  farther  from  the  basin,  are  much  less  productive 
than  the  Healdton  field. 

Loco,  Oklahoma. — The  Loco  field2  is  on  the  line  between 
Stephens  and  Jefferson  Counties,  Oklahoma,  about  3  miles  south- 
west of  the  village  of  Loco  and  10  miles  northwest  of  the  Healdton 
field.  For  many  years  asphalt  deposits  have  been  known  to  exist 
in  the  vicinity,  but  deep  drilling  was  not  begun  until  1912.  The 
first  gas  well  was  bored  in  the  spring  of  1913,  about  six  months 
before  the  Healdton  pool  was  discovered.  Six  other  gas  wells  of 
capacities  ranging  from  6,000,000  to  20,000,000  cubic  feet  a  day 

'POWERS,  SIDNEY:  The  Healdton  Oil  and  Gas  Field,  Oklahoma.  Econ. 
Geology,  vol.  12,  p.  604,  1917. 

WEGEMANN,  C.  H. :  The  Loco  Gas  Field,  Stephens  and  Jefferson  Counties, 
Oklahoma.  U.  S.  Geol.  Survey  Bull.  621,  pp.  31-42,  1915. 


322  GEOLOGY  OF  PETROLEUM 

have  been  drilled.  The  rocks  exposed  in  the  Loco  field  are  of 
Permian  age  and  consist  of  sandstone,  shale,  and  fine  conglomerate. 
The  structure  is  complicated,  an  anticline  being  crossed  by  a 
syncline.  The  gas  occurs  in  sands,  some  of  which  are  probably  of 
Permian  age.  Recently  some  heavy  oil  has  been  discovered. 

Duncan,  Oklahoma. — The  Duncan  gas  field,  known  also  as  the 
Hope  field,  is  in  Stephens  County,  Oklahoma,  about  10  miles 
northeast  of  the  town  of  Duncan  The  principal  flow  of  gas  is 
obtained  at  depths  of  about  850  feet,  and  the  wells  range  in  pro- 
duction from  3,000,000  to  almost  18,000,000  cubic  feet  a  day.1 
A  pipe  line  has  been  laid  from  the  field  to  Duncan  and  supplies 
that  town  with  gas. 

The  surface  rocks  in  the  Duncan  field  are  Red  Beds  of  Permian 
age.  They  consist  of  shale,  sandstone,  calcareous  sandstone,  and 
shale  conglomerate.  The  shale  is  red  or  bluish  gray  in  color.  The 
sandstone  is  predominantly  white  or  buff  but  is  in  some  places  red. 
The  cement  of  the  sandstone  is  calcareous,  and  in  some  beds  the 
lime  content  increases  in  amount  until  the  rock  is  a  calcareous 
sandstone. 

The  principal  gas-bearing  bed  in  the  Duncan  field,  a  sand  from 
7  to  19  feet  thick,  lies  800  to  900  feet  below  the  surface.  Showings 
of  gas  and  heavy  oil  in  small  quantity  are  obtained  in  some  of  the 
wells  in  shallower  sands.  The  gas  accumulation  lies  in  a  steeply 
plunging  anticline,  which  is  about  2  miles  broad  by  5  miles  long, 
and  whose  axis  trends  a  few  degrees  west  of  north. 

At  Granite,  Gotebo,  and  Wheeler  oil  or  gas  or  both  occur  in  or 
near  the  Red  Beds  close  to  the  unconformity  between  the  Penn- 
sylvanian  and  the  Permian. 

Lawton,  Oklahoma. — The  Lawton  oil  and  gas  field,  in  Comanche 
County,  Oklahoma,  is  near  the  east  end  of  the  Wichita  Mountains, 
about  5  miles  east  of  the  city  of  Lawton. 2  Oil  was  found  in  Lawton 
in  1901,  in  a  well  dug  for  water.  The  surface  rocks  are  Red  Beds, 
consisting  of  alternating  layers  of  shale  and  sandstone  and,  asso- 
ciated with  the  sandstone,  thin  layers  of  shale  conglomerate.  The 
wells  encounter  red  sandstone  and  shales. 

JWEGEMANN,  C.  H. :  The  Duncan  Gas  Field,  Stephens  County,  Oklahoma. 
U.  S.  Geol.  Survey  Bull  621,  p.  43,  1916. 

2WEGEMANN,  C.  H.,  and  HOWELL,  R.  W. :  The  Lawton  Oil  and  Gas  Field, 
Oklahoma.  U,  S.  Geol.  Survey  Bull  621,  p.  71,  1915. 


MID-CONTINENT  FIELDS 


323 


The  principal  anticlinal  axis  in  the  Lawton  field  extends  south- 
eastward from  the  Wichita  Mountains  and  is  interrupted  by  a  nar- 
row syncline,  which  crosses  it  almost  at  right  angles. 

Oil  and  gas  are  found  in  the  wells  of  the  Lawton  field  in  three 
different  sands,  which  are  known  in  the  field  as  the  " 200-foot," 
"400-foot,"  and  "800-foot"  sands.  The  "200-foot  sand"  is  from 
10  to  30  feet  thick  and  lies  at  depths  of  150  to  250  feet,  according 
to  the  location  of  the  well  with  reference  to  the  Lawton  anticline. 
This  sand  has  been  found  in  the  greater  number  of  the  wells  and 
generally  carries  at  least  a  show  of  oil.  Some  wells  are  said  to 
have  obtained  several  barrels  of  heavy  oil  from  this  sand,  and  gas 
also  is  reported  from  it,  though  only  in  small  quantity. 


RIOW 


R9  W 


R8W 


FIG.  139. — Map  showing  geologic  structure  and  distribution  of  wells  in 
Cement  field,  Oklahoma.  Contour  lines  show  altitude  of  Cyril  gypsum  bed. 
Contour  interval  50  feet.  (After  Clapp.) 

In  1916  many  wells  were  producing  small  amounts  of  oil. 
According  to  Wegemann  and  Heald,  the  oil  is  probably  derived 
from  Pennsylvanian  strata,  above  which  the  Red  Beds  lie  un- 
conformably. 

Cement,  Oklahoma.— The  Cement  field1  is  in  Caddo  County, 
Oklahoma,  northeast  of  the  Wichita  Mountains  and  60  miles 

'CLAPP,  F.  G. :  Geology  of  Cement  Oil  Field.  Min.  and  Met.,  No.  158,  sec. 
27,  pp.  1-9,  February,  1920. 


324  GEOLOGY  OF  PETROLEUM 

northwest  of  Healdton.  It  is  in  the  Keeche  Hills,  which  rise  some 
400  or  500  feet  above  the  surrounding  country.  The  field  is  on  an 
anticline  over  13  miles  long  and  from  1  to  3  miles  wide.  The  major 
axis  trends  N.  75°  W.  from  the  village  of  Cement,  but  east  of  the 
village  appears  to  be  deflected  to  about  S.  45°  E.  (See  Fig.  139.) 
The  anticline  has  an  undulatory  crest,  and  several  of  the  wells  sunk 
at  the  high  places  on  the  crest  have  yielded  much  gas  and  some  oil. 
The  surface  rocks  are  Permian  Red  Beds,  with  gypsum.  The 
base  of  the  Permian  series  is  thought  to  lie  about  2,700  feet  from 
the  surface,  but  some  place  it  at  1,700  feet.  The  oil  and  gas  are 
found  in  the  lower  part  of  the  Permian,  in  sandstones  covered  by 
shale. 

Madill,  Oklahoma.  —  The  Madill  pool,  in  Marshall  County, 
Oklahoma,1  is  just  south  of  the  Arbuckle  uplift.  The  region  in- 
cludes the  Tishomingo  granite  and  Paleozoic  and  Cretaceous  sedi- 
ments. The  Paleozoic  sedimentary  rocks  rest  unconformably  on 
the  eroded  surface  of  the  granite.  They  are  folded  and  faulted 
and  are  overlain  by  the  Cretaceous  rocks,  which  are  but  slightly 
tilted.  (See  Fig.  140.)  The  lowest  and  thickest  Cretaceous  forma- 
tion is  the  Trinity  sand.  It  is  a  compact  but  unconsolidated, 
moderately  fine  sand  with  a  little  clay  and  bands  of  sandy  clay. 

Oil  seeps  and  bituminous  saturated  sands  are  found  in  the 
region.  The  principal  oil-bearing  stratum  is  at  or  near  the  base 
of  the  Trinity  sand,  a  little  more  than  400  feet  below  the  surface 
at  Madill.  It  is  a  porous  bed  of  sand  and  gravel  in  which  the 
particles  and  pebbles  are  not  cemented. 

Of  four  producing  wells  brought  in  to  April  1909,  one  had  an 
initial  flow  of  several  hundred  barrels.  The  oil  is  very  light,  hav- 
ing a  specific  gravity  of  47.5°  B.,  and  is  rich  in  gasoline  and  kero- 
sene. Taff  and  Reed  believe  that  the  oil  and  asphalt  are  derived 
from  the  Carboniferous  strata  which  are  tilted  so  that  their  edges 
project  against  the  Trinity  sand. 

Wichita  and  Clay  Counties,  Texas.  —  The  productive  pools  of 
Wichita  County,  Texas,  include  Burkburnett,  Electra,  Fowlkes, 
and  Iowa  Park.  These  pools  are  in  areas  of  Permian  rock,  below 
which  are  strata  of  Pennsylvanian  age. 


,  J.  A.  :  U.  S.  Geol.  Survey  Geol  Atlas,  Tishomingo  folio  (No.  98),  1903. 
TAFF,  J.  A.,  and  REED,  W.  J.  :  The  Madill  Oil  Pool,  Oklahoma.     U.  S.  Geol. 
Survey  Bull.  381,  pp.  504-513,  1910. 


MID-CONTINENT  FIELDS 


325 


Scale: 


'We// 

isHfe// 

y/fc/e 


o  locat/oncfrt/Jffng 
•       Tank  W 


326  GEOLOGY  OF  PETROLEUM 

The  Electra  field1  is  in  the  western  part  of  Wichita  County,  near 
the  Oklahoma  line.  The  first  reported  occurrence  of  oil  in  this 
field  was  in  a  well  dug  in  1900  for  water,  north  of  what  was  then 
Beaver  station;  this  well  found  oil  at  147  feet.  South  of  the  station 
another  well  found  a  little  oil  at  205  feet.  Since  that  date  the  area 
has  been  developed  into  a  steadily  productive  field,  yielding  oil  of 
high  grade.  The  outcropping  rocks  are  of  Permian  age,  probably 
near  the  base  of  the  Permian.  The  strata  consist  of  shale  and 
sandstone,  with  some  limestone  beds,  and  are  referred  to  the 
Albany-  Wichita  by  Udden.  (See  Fig.  141.)  Below  the  Permian 
beds  are  Pennsylvanian  shale,  clay,  and  sandstone,  with  thin  beds 
of  limestone. 

Oil  and  gas  are  found  in  the  Permian  (Wichita  formation,  as 
stated  by  Udden),  in  the  Pennsylvanian,  and  possibly  in  the  Mis- 
sissippian.  The  structure  of  the  district  is  that  of  a  broad  anti- 
cline with  a  wide,  and  at  places  nearly  flat  crest. 

Burkburnett,  which  lies  northeast  of  Electra,  is  one  of  the  most 
productive  fields  in  the  Mid-Continent  region.  It  is  said  to  lie  on 
a  broad  anticline,  which  at  some  places  is  probably  complicated  by 
faulting.  It  produces  oil  of  good  grade,  rich  in  gasoline.  A  small 
part  of  the  oil  comes  from  beds  that  have  been  correlated  with  the 
Permian.  The  remainder  is  derived  from  deeper  beds.  In  1916  and 
later  many  wells  yielding  from  1,000  to  2,000  barrels  a  day  in  flush 
production  were  encountered  between  1,700  and  2,000  feet.  The 
details  of  the  structural  features  of  this  district  are  not  available  to 
me.  The  broader  features  of  the  uplift  are  treated  by  Lee  Hager.  2 

The  Petrolia  field3  (Fig.  142)  is  in  the  northern  part  of  Clay 
County,  12  miles  north  of  Henrietta.  The  outcropping  rocks  are 
Red  Beds  of  the  Wichita  formation  and  consist  of  shales  and  sand- 
stones. These  beds  overlie  the  Cisco  shale,  of  the  Pennsylvanian, 
which  consists  of  sandstones,  clays,  and  shales  and  contains  the 
oil  and  gas  sands.  As  shown  by  Udden  and  Phillips,  4  the  structure 


,  j.  A.  :  A  Reconnaissance  Report  on  the  Geology  of  the  Oil  and  Gas 
Fields  of  Wichita  and  Clay  Counties,  Texas.  Texas  Univ.  B-ull.  246,  1912. 

2HAGER,  LEE:  Red  River  Uplift  Has  Another  Angle.  Oil  and  Gas  Jour., 
vol.  18,  pp.  64-65,  1919. 

3SnAW,  E.  W.  :  Gas  in  the  Area  North  and  West  of  Fort  Worth.  U.  S.  Geol. 
Survey  Bull.  629,  pp.  1-75,  1916. 

4UDDEN,  J.  A.,  and  PHILLIPS,  D.  McN.  :  A  Reconnaissance  Report  on  the 
Geology  of  the  Oil  and  Gas  Fields  of  Wichita  and  Clay  Counties,  Texas. 
Texas  Univ.  Bull.  246,  1912. 


MID-CONTINENT  FIELDS 


327 


VERTICAL    SCM.C 


328 


GEOLOGY  OF  PETROLEUM 


is  anticlinal.  There  are  three  principal  sands  yielding  gas  or  oil 
and  gas.  The  average  original  pressure  was  725  pounds  to  the 
square  inch.  Although  the  field  has  produced  principally  gas  it 
has  yielded  also  over  3,000,000  barrels  of  oil.  The  oil  is  light  and 
of  good  grade.  . 


FIG.  142.— Structure  contour  map  of  Petrolia  oil  and  gas  field,  Texas.  (After 

Shaw.) 


NORTH  CENTRAL  TEXAS  FIELDS 


The  oil  fields  that  lie  entirely  or  partly  in  Texas  (Fig.  143)  are 
grouped  as  follows: 

1.  Red  River  region  of  northern  Texas  and  southern  Oklahoma. 

2.  North-central  Texas  fields,  including  Strawn,  Allen,  Duke,  Caddo,  Veale, 
Ranger,  Breckenridge,  Moran,  Santa  Anna,  Brownwood,  Trickham,  Lohn, 
and  others. 

3.  Fields  in  the  Upper  Cretaceous  area  east  of  the  I^alcones  fault. 

4.  Western  part  of  Sabine  uplift  in  Texas  and  Louisiana. 

5.  Gulf  coast  fields. 


MID-CONTINENT  FIELDS 


329 


The  north-central  Texas  fields1  as  developed  in  1919  were  prac- 
tically coextensive  with  the  belt  of  Pennsylvanian  strata  that 
extends  northward  from  the  Llano-Burnet  uplift  nearly  to  the 
Oklahoma  line.  (See  Fig.  144.)  In  nearly  all  the  oil  districts 
the  outcropping  rocks  are  Pennsylvanian.  These  generally  dip 
northwest  at  low  angles.  Toward  the  east  the  Pennsylvanian  is 
overlapped  by  the  Trinity  sand  (Lower  Cretaceous).  Toward  the 
west  it  is  overlain  by  Permian  strata.  Below  the  Pennsylvanian 
is  found  the  Bend  series,  which  crops  out  in  the  Llano  uplift  but 
which  is  buried  to  the  north.  This  series  is  unconformable  with 


/.  Humble 

2.  Day  ton 

3.  Sour  Lake 

4.  Saratoga 
S.oatson 

6  Spindle top 
J.  Goose  Creek 


. 
Markh&m 


9.  Thrctll 

lO.Morotn 

II.  Strawn 

K.ffecrraandBurkk 

/3.  Petrolic* 

!4.Corsicana 

IB.  Mexia  Gc*s  Field 

l(>  Port  of  Cacfo/o  Field 


17.  Orange 
IS.  Holiday 
tf.WilbotrgerCo. 
20. San  Antonio 
Zl.Trickham 
22.Santc*Anria 
Z3.RiserOa$  Field 
^.Jennings  6a$  Field 


26.  Damon  Mound 

27.  8reckenrio/ge 
ZS.Ccrcfafo  P.O. 
&  Hoi  solo 


31.  South  Bosque 


FIG.  143. — Sketch  map  of  Texas  and  Louisiana,  showing  location  of  certain 
oil  and  gas  fields.  (After  Gardner.}  For  more  detailed  maps  see  Figs.  137, 
150,  152,  155,  156  and  160. 

the  overlying  Pennsylvanian,  as  is  indicated  by  the  section  in 
Fig.  145. 

The  general  character  of  the  Carboniferous  formations  is  shown 

^ILL,  R.  T. :  Geography  and  Geology  of  Black  and  Grand  Prairies,  Texas. 
U.  S.  Geol.  Survey  Twenty-first  Ann.  Rept.,  part  7,  pp.  1-666, 1900. 

WEGEMANN,  C.  H. :  A  Reconnaissance  in  Palo  Pinto  County,  Texas.  U.  S. 
Geol.  Survey  Bull.  621,  pp.  51-59,  1912. 

MATTESON,  W.  G. :  A  Review  of  the  Development  in  the  New  Central  Texas 
Oil  Fields  During  1918.  Econ.  Geology,  vol.  14,  pp.  95-146, 1919. 

HAGER,  DORSET  :  Geology  of  the  Oil  Fields  of  North-Central  Texas.  Am. 
Inst.  Min.  Eng.  Bull.  133,  pp.  1109-1118,  1918. 


330 


GEOLOGY  OF  PETROLEUM 


in  the  sections  on  page  335.  Sandstones  are  more  abundant  in  the 
lower  part  of  the  series  and  toward  the  east.  In  the  Canyon  for- 
mation limestones  increase  toward  the  south.  In  the  Cisco  also 
limestones  increase  toward  the  west  and  south.  In  Pennsylvanian 
time  the  Arbuckle  Mountains  and  some  area  toward  the  east  and 


BULLETIN  450    Pt_*TE. 


FIG.  144. — Geologic  map  of  Texas.  (After  Hill,  Willis,  Paige  and  others.) 

south,  now  buried,  appear  to  have  been  the  main  sources  of  sedi- 
ments of  north-central  Texas,  rather  than  the  Llano  area.  The 
region  of  what  is  now  the  Ouachita  orographic  element  was  doubt- 
less a  land  area  of  large  size,  as  it  appears  to  have  supplied  material 


MID-CONTINENT  FIELDS  331 

for  sediments  far  to  the  north,  toward  the  Ozarks,  and  far  to  the 
south,  toward  the  Llano  Mountains.  Its  influence  on  sedimenta- 
tion was  more  far-reaching  than  that  of  the  Ozark  uplift  or  the 
Llano  uplift.  Its  influence  on  structure,  on  the  other  hand,  was 
more  narrowly  confined  than  that  of  either  the  Ozark  or  the  Llano 
center.  Mississippian  and  Pennsylvanian  beds  dip  north  from 
the  Llano  element  to  the  northern  parts  of  Young  and  Jack 
Counties. 

The  dominant  structural  feature  in  the  northern  Texas  field  is  a 
monocline  dipping  northward  from  the  Llano  uplift  at  about  25 
feet  to  the  mile.  On  this  monocline  is  superimposed  a  low  arch 
that  extends  from  the  Llano-Burnet  region  northward  about  150 
miles.  This  arch  is  more  accentuated  in  the  Bend  series  than  in 
the  overlying  rocks,  and  has  been  designated  the  Bend  arch.  Its 
origin  is  uncertain.  It  is  on  the  monocline  that  was  formed  by 


FIG.  145. — Section  of  Bend  arch,  north-central  Texas.  (After  Hager.) 

the  upthrust  of  the  Llano  element,  and  it  extends  northward  from 
that  element,  but  it  is  no  more  accentuated  at  the  south  end  than 
it  is  150  miles  farther  north.  One  hypothesis,  based  on  data  that 
are  not  as  complete  as  might  be  wished,  accounts  for  its  origin, 
by  assuming  two  periods  of  warping. 

The  vertical  scale  in  Fig.  145  is  exaggerated  about  25  times. 
The  dip  of  the  Pennsylvanian  strata  is  much  lower  than  is  indi- 
cated. Before  the  deposition  of  the  Pennsylvanian  the  Bend 
formation  was  probably  almost  flat-lying  or  dipped  gently  north- 
west. After  Cretaceous  time  the  Bend  was  tilted  eastward,  as 
were  also  the  Cretaceous  beds. 

The  Bend  arch  (Figs.  146-149)  has  been  the  subject  of  much 
discussion.  Maps  of  the  structure  are  presented  as  expressed  by 


332 


GEOLOGY  OF  PETROLEUM 


Grehctous 

I  Upper  Cr*h«ou» 


Carbon.ferou* 
I  Permian 
]Penniy!»ani«A 
)  Mississippi*  r 


Cambro-OrtJov.tan 
KM  Prt  C»mbrl«n 
ESS  b'rU 


/  Oil  Ir  68S  PooU 

e  County  Stah 


FIG.  146.  —  Geologic  map  of  north-central  Texas.   (After  Hager.)  For  sections 
along  A-  A,  B-B  and  C-C  see  Figs.  147-149. 


MID-CONTINENT  FIELDS 


333 


E;vst 


FIG.  147. — Section  across  southern  part  of  Bend  Arch,  Texas,  alone  line  A-A 

Fig.  146. 


West 


Putnam -Mineral  Wells  Section     B-  B 


FIG.  148. — Section  across  northern  part  of  Bend  Arch,  Texas,  along  line  B-B. 

Fi.  146, 


s.w. 


0  Miles  10  20  30  40  50 


6ea  Lere]=  0 


FIG.  149.— Section  along  axis  of  Bend  Arch,  Texas,  along  line  C-C,  Fig.  146. 


334 


GEOLOGY  OF  PETROLEUM 


Eager  and  others.     Pratt1  denies  the  existence  of  data  showing  the 
presence  of  the  Bend  arch  farther  north  than  Eastland  County. 


PINTO 


FIG.  150. — Sketch  map  of  Eastland,  Stephens  and  parts  of  adjoining 
counties,  Texas,  showing  axes  of  oil  and  gas  pools  as  interpreted  by  Matteson. 
Dashed  outlines  are  not  structural  lines  but  indicate  main  oil-bearing  areas  as 
developed  in  spring  of  1819.  (After  Matteson.} 

IPBATT,  W.  E. :  Geologic  Structures  and  Producing  Areas  in  North  Texas 
Petroleum  Fields,  with  Discussion  by  HILL,  SCHUCHERT,  FULLER,  CUMMINGS, 
BEAL,  PEPPERBERG,  and  others.  Am.  Assoc.  Pet.  Geol.  Bull.  3,  pp.  45-70, 
1919. 


MID-CONTINENT  FIELDS 


335 


McUeiky 

Davis         Tex.*  Pae.     Bjawer    Braehear       Allen 

No.1         aO.4Q.Co.      No.1          No.1          N«.l 

Tex.4  Pao.       Ranger      T«.4  Pac.  McAllister  bun  Co. 


[nit  Prod,    "t" 

=  1012  bbls. 
Smithn  ick  Shale 
Oil 

Init-Prod.  _  200  bbln. 

Drilled  to  Top  Black  lime 

•t  3GOO  Dcv.  19,1918 


EUenberger 
Limestone 
Cambro-Ordov. 


Init.  Prod. 

•  S-10,000,000  ou.ft.gat 

800  bbl  a.  Oil  Dal]/ 

FIG.  151. — Logs  of  certain  wells  in  north-central  Texas  fields.  The  terms 
"Marble  Falls,"  "Black  Lime,"  and  "Bend  Lime,"  are  used  synonymously 

(rtfiai*   Ajf ntt*! O^»/M\     * *T)**r\c*r\r\4-  "D»«*-kj-lm^4-*x^»^ "  nui*ni<  ^nrincr    1Q1Q 


Ioi,Prod,  .   5-T.OOO.OOO  ou.ft.ga, 
Now  Producing  500  bbl,  /  Day  Oil 


,  , 

(after  Mattisori)    "Present  Production 


336  GEOLOGY  OF  PETROLEUM 

Briefly,  the  Ranger  region  is  a  broad  monocline  dipping  north- 
westward, on  which  is  superimposed  the  Bend  arch,  with  its  axis 
gently  plunging  north.  At  numerous  places  small  wrinkles  are 
found  on  the  arch.  Oil  is  concentrated  below  these  wrinkles, 
especially  below  small  open  anticlines.  Few  of  the  anticlines  close 
at  the  surface,  but  the  folds  become  more  acute  below  the  sur- 
face, so  that  certain  folds  which  do  not  close  at  the  surface  close  in 
depth.  Moreover,  owing  to  the  unconformities  present,  some 
folds  found  in  depth  may  not  be  expressed  at  the  surface,  although 
those  found  at  the  surface  are  generally  expressed  in  depth. 

According  to  Matteson,  the  Bend  arch  is  not  marked  by  a  single 
axis  but  consists  of  several  closely  spaced  parallel  folds.  He  states 
that  in  Stephens  and  Eastland  Counties  there  are  three  axes  (Fig. 
150).  On  the  east  axis  are  the  Strawn,  Allen,  and  Duke  pools. 
West  of  this  and  parallel  to  it  is  a  second  axis  on  which  are  the 
Caddo,  Veale,  and  Ranger  pools.  Still  farther  west  is  a  third  axis 
on  which  are  the  well  of  Black  Brothers,  in  the  northern  part  of 
Stephens  County,  and  the  pool  south  of  Breckinridge.  Records  of 
the  Black  well  and  other  wells  in  this  area  are  shown  in  Fig.  151. 

There  is  little  surficial  evidence  that  petroleum  exists  in  the 
strata  underlying  the  area  containing  the  Ranger  and  associated 
districts.  Asphalt  and  oil  seeps  are  rare  or  lacking.  About  100 
miles  to  the  south,  in  the  Llano-Burnet  region,  according  to  Paige, 
the  Carboniferous  strata  have  a  strong  petroliferous  odor.  A  small 
oil  seep  in  a  spring  near  the  town  of  Burnet  has  deposited  at  the 
surface  asphaltic  material  in  the  cracks  and  interstices  of  the 
neighboring  limestones.  In  Post  Mountain  also,  just  west  of 
Burnet,  a  little  oily  residue  is  found  about  20  feet  above  the  base 
of  the  Cretaceous,  and  it  is  possible  that  oil  has  passed  from  the 
underlying  Carboniferous  into  the  porous  Trinity  sand  and  spread 
laterally.  1 

Oil  is  obtained  at  eight  horizons  in  north-central  Texas.  Of 
these,  according  to  Matteson,  2  one  is  at  the  base  of  the  Canyon  or 
top  of  the  Strawn;  another  is  in  the  middle  of  the  Strawn;  another 
comprises  sand  lenses  in  the  Smith  wick  shale;  another  is  at  the 
contact  between  the  Smith  wick  and  the  Marble  Falls  limestone; 
and  below  that  are  four  sands  included  in  the  Marble  Falls.  These 


,  SIDNEY:  Mineral  Resources  of  the  Llano-Burnet  Region,  Texas. 
U.  S.  Geol.  Survey  Bull  450,  p.  93,  1911. 
*Econ.  Geology,  vol.  14,  pp.  132-134,  1919. 


MID-CONTINENT  FIELDS  337 

sands  are  probably  lenticular,  and  different  sands  are  productive 
in  different  wells.  Slight  structural  irregularities  on  the  surface, 
such  as  noses,  terraces,  and  minor  wrinkles,  generally  indicate  more 
accentuated  features  at  greater  depths,  and  drilling  them  has  fre- 
quently revealed  oil.  At  some  places  drilling  has  revealed  struc- 
tural features  that  have  no  surface  indications.  Most  of  the  wells 
yield  gas,  and  in  many  of  them  the  oil  issues  under  high  pressure. 
Salt  water  has  been  encountered  in  several  wells.  The  initial 
production  of  many  wells  is  large,  and  the  oil  is  of  exceptionally 
high  grade. 

Owing  partly  to  the  escape  of  gas  in  wells,  the  pressure  has 
declined  in  this  region.  The  absence  of  sufficient  gas  to  force  the 
oil  into  the  borings  has  resulted  in  an  exceptionally  rapid  decline 
in  the  yield  of  oil  wells  in  some  of  the  fields  that  were  originally 
highly  productive. 

The  oil  at  Ranger  and  in  other  central  Texas  fields  is  a  high- 
grade,  light  gravity  (34°-40°  B.)  crude  oil  of  an  olive-green  color. 
An  analysis1  shows  the  following  percentage  of  ingredients  for 
Ranger  crude: 

Gravity  38.5°  Baume"  at  60°  F. 

Gasoline 22. 0  per  cent,  59. 9°  gravity 

Naphthas 3 . 8  per  cent,  52 . 3°  gravity 

Kerosene 21 . 8  per  cent,  43 . 9°  gravity 

Residue  (lubricating  and  fuel  oil  not 
separated) 52. 0  per  cent,  27 . 9°  gravity  . 

FIELDS  EAST  OF  BALCONES  FAULT 

General  Features.— The  Balcones  fault  zone  (Fig.  152)  extends 
from  Hunt  County,  northeastern  Texas,  southwestward  to  Bexar 
County,  a  distance  of  nearly  300  miles.  The  rocks  involved  are 
strata  of  the  Lower  and  Upper  Cretaceous  series,  of  which  a  sec- 
tion is  given  on  page  340.  Oil  or  gas  or  both  are  found  m  the 
Navarro  formation,  Taylor  marl,  and  Woodbine  sand.  In  the 
Caddo  field,  Louisiana,  the  west  edge  of  which  extends  into  Marion 
County,  Texas,  much  oil  is  obtained  from  the  Woodbine  sand. 
In  some  places  in  the  Balcones  region  the  Woodbine  carries  water 
that  is  only  slightly  saline  but  no  oil. 

»MATTESON,  W,  G,:  Op.  tit.,  p.  131. 


338 


GEOLOGY  OF  PETROLEUM 


The  fault  zone,  as  stated  by  Hill, 1  consists  of  a  number  of  nearly 
parallel  step  faults  or  small  jogs,  the  aggregate  displacement  of 


/I  ana/ 
gas  fielat 


to          39  MILES 


FIG.  152. — Sketch  map  showing  part  of  Balcones  fault  region,  Texas.   (Data 
from  Hill,  Matson,  Hopkins  and  others.) 

lHiLL,  R.  T. :  Geography  and  Geology  of  the  Black  and  Grand  Prairies, 
Texas.    U.  S.  Geol.  Survey  Twenty-first  Ann.  Rept.,  part  7,  p.  382,  1901. 


MID-CONTINENT  FIELDS  339 

which  attains  a  maximum  of  1,000  feet.  This  zone  is  limited 
nearly  everywhere  on  the  west  by  a  larger  fault,  which  at  Austin 
has  a  downthrow  of  nearly  500  feet.  This  zone  is  a  number  of 
short  faults  overlapping  en  echelon.  The  fault  line  from  the 
Nueces  River  to  the  Brazos  River  marks  the  dividing  line  between 
the  Black  and  Grand  prairies.  North  of  Waco  it  passes  into  the 
unconsolidated  clays  of  the  Black  Prairie  between  Whitney  and 
Aquilla. 

The  fault  generally  dips  southeast,  and  the  downthrow  is  on  the 
southeast  side.  In  the  zone  of  deformation  east  of  the  fault  there 
are  small  folds  in  which  oil  or  gas  or  both  are  concentrated.  In 
this  zone  is  the  Corsicana  field,  which  embraces  the  Burke,  Eden, 
Powell,  and  Chat  field  pools  and  other  small  pools  near  by.  South 
of  the  Corsicana  field,  in  Limestone  County,  is  the  Mexia-Groes- 
beck  gas  field,  west  of  which,  in  McLennan  County,  is  the  South 
Bosque  field,  and  south  of  that  the  Thrall  and  Elgin  fields.  About 
100  miles  southwest  of  Elgin  is  a  small  field  near  San  Antonio, 
where  gas  and  heavy  oil  are  found  in  the  Nacatoch  sand  and  the 
Annona  chalk. 

Corsicana  Field.  —  The  Corsicana  oil  and  gas  field,1  in  Navarro 
County,  extends  from  Corsicana  eastward  to  Powell  and  from  the 
vicinity  of  Angus  northward  to  Chatfield.  Productive  pools  hav- 
ing an  aggregate  area  of  nearly  50  square  miles  have  been  devel- 
oped in  a  field  that  measures  20  miles  from  north  to  south  and  10 
miles  from  east  to  west.  Oil  was  first  discovered  in  the  city  of 
Corsicana,  in  a  search  for  water  supply.  The  field  was  gradually 
extended  eastward  and  has  been  productive  since  1895. 

A  section  showing  tfoe  strata  in  this  field  is  given  below. 


,  G.  C.,  and  HOPKINS,  O.  B.:  The  Corsicana  Oil  and  Gas  Field, 
Texas.  U.  S.  Geol.  Survey  Bull  661,  pp.  211-272,  1918. 

MILLER,  T.  D.  :  The  Recently  Developed  Oil  Field  of  Texas.  Eng!  and  Min. 
Jour.,  June  18,  1898,  pp.  734-735. 

OLIPHANT,  F.  H.  :  U.  S.  Geol.  Survey  Nineteenth  Ann.  Rept.,  part  6,  con- 
tinued, pp.  102-105,  1898. 

PHILLIPS,  W.  B.:  Texas  Petroleum.  Texas  Univ.  Min.  Survey  Bull.  1, 
pp.  6,  36-42,  1900. 

ADAMS,  G.  I.:  Oil  and  Gas  Fields  of  the  Upper  Cretaceous  and  Tertiary 
Formations  of  the  Western  Gulf  Coast.  U.  S.  Geol.  Survey  Bull  184,  pp. 
54-55,  1901. 

HARRIS,  G.  D.  :  Oil  and  Gas  in  Louisiana.  U.  S.  Geol.  Survey  Bull.  429, 
pp.  31,  34,  1910. 


340 


GEOLOGY  OF  PETROLEUM 


GENERALIZED  SECTION  OF  FORMATIONS  IN  THE  CORSICANA  OIL  AND  GAS 
FIELD,  TEXAS'*       (After  Matson  and  Hopkins) 


System 

Series 

Group 

Formation 

Thickness 
(Feet) 

Character 

Recent. 

Alluvial    deposits    along 

streams. 

Pleistocene. 

Terrace  deposits. 

Tertiary. 

Eocene. 

Midway  forma- 
tion. 

250-500 

Micaceous  sandy  clays, 
fine  argillaceous  sands, 
and  limestone  concre- 
tions. 

Navarro  forma- 
tion. 

1      OQA     0    Of\f) 

Light  to  dark  gray  cal- 
careous clay,  sandy 
clay,  and  fine  lenticu- 
lar beds  of  sand. 

Taylor  marl. 

Massive  calcareous  clay 
marl,  little  sand,  and 
glauconite. 

Gulf  (Uppei 
Cretace- 
ous). 

Austin  chalk. 

400-503 

Gray  to  white  chalky 
limestone  containing 
some  hard  beds. 

Eagle   Ford 
shale. 

300-400 

Light  to  dark  colored 
shale  or  clay  and  thinly 
laminated  impure  lime- 
stone. 

Woodbine  sand. 

400-450 

Sand,  sandy  lignitic  clay, 
sandstone,  ferruginous 
sand,  and  clay. 

Denison  forma- 
tion. 

150-200 

Clay  and  limestone. 

Cretaceous. 

Washita. 

Fort     Worth 
limestone. 

25-75 

Alternating  beds  of  lime- 
stone and  marl. 

Preston    forma- 
tion. 

50-100 

Calcareous  laminated 
clays  and  impure  lime- 
stone. 

Comanche 
(Lower 
Cretace- 

Fredericks- 

Edwards     lime- 
stone. 

Comanche  Peak 
limestone. 

300-400 

White  chalky  limestones, 
variously  indurated, 
and  in  places  fine  are- 
naceous beds. 

ous). 

Walnut  clay. 

100-200 

Calcareous  clays  and  im- 
pure marly  and  chalky 
limestones. 

Paluxy  sand. 

125-200 

Fine-grained  sand  and 
lenticular  beds  of  clay. 

Glen  Rose  lime- 
stone. 

300-500 

Impure  limestone,  marl, 
and  calcareous  shales. 

Travis  Peak 
sand. 

250  * 

Conglomerate,  sand, 
sandstone,  shales,  and 
impure  limestones. 

"The  formations  below  the  Navarro  formation  crop  out  west  of  the  Corsicana  field  and  dip 
under  it.  The  Upper  Cretaceous  formations  have  been  penetrated  by  the  drill  in  this  field  and 
are  known  from  well  records;  the  Lower  Cretaceous  formations  have  not  been  penetrated  by 
the  drill  in  this  field  but  are  known  from  outcrops  and  well  records  west  of  the  field.  The  data 
relating  to  the  Lower  Cretaceous  are  taken  largely  from  a  report  by  R.  T.  HILL  (Geography  and 
Geology  of  the  Black  and  Grand  Prairies,  Texas.  U.  S.  Geol.  Survey  Twenty-first  Ann.  Rept., 
part  7,  1901). 


MID-CONTINENT  FIELDS  341 

The  oil  and  gas  in  the  Corsicana  field  are  obtained  from  the 
upper  part  of  the  Upper  Cretaceous,  the  light  oil  and  the  gas  in  the 
Corsicana  oil  pool  and  in  the  Chatfield  and  Edens  gas  pools  near 
by,  probably  coming  from  the  Taylor  marl  and  the  heavy  oil  and 
the  gas  in  the  other  pools  from  the  Navarro  formation.  The  rela- 
tion of  the  oil  and  gas  to  the  geologic  structure  varies  from  place 
to  place;  as  stated  by  Matson  and  Hopkins  accumulation  is  con- 
centrated where  there  are  well-developed  anticlines,  such  as  occur 
in  some  parts  of  the  field  that  yield  heavy  oil.  The  distribution  of 
oil  and  gas  is  also  influenced  by  variations  in  the  porosity  of  the 
sand,  though  these  variations  are  not  as  numerous  as  in  some  other 
regions. 

The  strata  in  the  Corsicana  field  dip  in  general  to  the  southeast 
at  a  rate  of  50  to  100  feet  to  the  mile.  The  uniformity  in  direction 
and  amount  of  dip  is  interrupted  at  a  number  of  places  by  folds, 
none  of  which  are  continuous  over  large  areas.  The  greatest  dips 
observed  on  the  folds  are  at  the  rate  of  560  feet  to  the  mile.  The 
high  dips  are  confined  to  small  areas.  The  folds  trend  in  two 
directions — one  approximately  parallel  to  the  dip  of  the  rocks  and 
the  other  at  right  angles  to  it.  There  is  no  evidence  of  faulting. 

The  structure  of  the  pool  south  of  Chatfield  shows  an  irregular 
anticline  that  trends  northeast  and  is  2  miles  long  and  about  three- 
quarters  of  a  mile  wide.  The  dips  on  its  flanks  are  as  much  as  2°. 
The  accumulation  of  gas  is  in  the  crest  of  the  anticline  and  is 
backed  up  on  all  sides  by  salt  water. 

The  Witherspoon-McKie  pool,  southwest  of  Powell,  lies  along 
the  crest  of  a  low,  flat-topped  anticline  that  extends  from  the 
southeastern  part  of  the  Witherspoon  tract  south  west  ward  1J^ 
miles  to  the  McKie  tract.  The  depth  to  the  highest  productive 
sand  is  825  to  875  feet,  and  to  the  lowest  (1918)  about  100  feet 
more.  Oil  and  gas  were  present  only  along  the  crest  of  the  anticline, 
and  water  was  troublesome  over  practically  the  entire  pool.  Gas 
was  present  originally  in  both  the  upper  and  lower  sands,  but  more 
abundantly  in  the  lower.  All  the  wells  at  the  north  end  of  the 
pool  have  been  invaded  by  salt  water  and  abandoned. 

The  Burke  pool,  1  mile  south  of  Powell,  is  associated  with  the 
most  pronounced  fold  that  has  been  found  in  the  Corsicana  field. 
This  fold,  which  is  probably  a  shortened  anticline  or  dome,  has 
dips  of  about  185  feet  to  the  mile  to  the  northwest,  southwest,  and 
southeast.  Oil  occurs  in  the  upper  part  of  the  fold,  where  the 


342  GEOLOGY  OF  PETROLEUM 

upper  sand  is  from  about  400  to  480  feet  below  sea  level.  Where 
the  sand  is  more  than  480  feet  below  sea  level  it  is  generally  sat- 
urated with  brine,  although  in  that  area  a  number  of  wells  have 
yielded  some  oil. 

Mexia-Groesbeck  Field. — The  Mexia-Groesbeck  gas  field  is  in 
the  east-central  part  of  Limestone  County,  Texas,  where  it 
occupies  an  area  having  an  approximate  length  of  12^  miles  and 
an  approximate  width  of  0.9  mile. 1 

Production  began  in  1912.  Prior  to  the  drilling  of  the  first  wells 
gas  had  been  known  in  a  few  shallow  water  wells  west  of  the  field 
and  had  been  exploited  in  the  vicinity  of  Corsicana.  Wells  show- 
ing considerable  volumes  of  gas  had  also  been  drilled  between 
Corsicana  and  Mexia,  but  salt  water  interfered  with  development. 

The  wells  in  the  Mexia-Groesbeck  gas  field  pass  through  the 
lower  Eocene  Midway  formation  and  penetrate  a  portion  of  the 
Upper  Cretaceous  Navarro  formation.  The  Midway  consists  of 
clay,  limestone,  and  sand.  Layers  of  the  limestone  are  exposed 
on  eroded  surfaces,  and  where  the  surface  is  level  the  successive 
layers  form  bands  that  are  roughly  parallel. 

The  upper  part  of  the  Navarro  formation,  which  underlies  the 
Midway,  is  composed  of  clays  and  shales  with  thin  beds  of  sand 
and  sandstone. 

The  gas  sand  of  the  Mexia-Groesbeck  field  is  the  Nacatoch  sand 
member  of  the  Navarro  formation,  correlated  with  the  Nacatoch 
sand  of  northwestern  Louisiana  and  southwestern  Arkansas.  The 
Nacatoch  sand  in  the  Mexia-Groesbeck  field,  as  shown  by  C.  E. 
Van  Orstrand,  contains  from  16.6  to  34.2  per  cent  of  pore  space, 
with  an  average  of  25.5  per  cent,  which  would  amount  to 
2,331,057,000  cubic  feet  for  the  entire  field.  Only  a  small  part  of 
that  amount  belongs  to  the  undeveloped  area,  the  largest  part  of 
it  being  in  the  developed  areas.  The  entire  pore  space  of  the  gas 
sand  was  probably  occupied  by  gas,  because  the  pressure  when  the 
field  was  first  developed,  276  pounds  to  the  square  inch,  was 
sufficient  to  force  the  gas  into  minute  pores.  The  generally  uni- 
form decline  of  pressure  throughout  the  field,  as  stated  by  Matson, 
indicates  a  uniformly  porous  rock.2 

'MATSON,  G.  C. :  Gas  Prospects  South  and  Southeast  of  Dallas.     U.  S,  Geol. 
Survey  Bull.  629,  p.  87,  1916. 
WATSON,  G.  C. :  Op.  cit.,  p  92. 


MID-CONTINENT  FIELDS 


343 


Thrall  Field. — The  Thrall  oil  field  is  about  a  mile  southeast  of 
Thrall,  Williamson  County,  Texas.1  Oil  was  discovered  here  in 
1914  in  a  well  sunk  for  water,  and  the  district  soon  developed  into 
a  productive  field.  The  outcropping  rock  is  the  Taylor  marl  of 
the  Upper  Cretaceous  series,  which  dips  east  to  southeast  at  60  to 
100  feet  to  the  mile.  The  strata  above  the  oil-bearing  rock  consist 


, 


/ 


a  (//./.( 


PRODUCTION  IN  BARRCW  PIK  OKf, 
X  DRY  MOL6. 

•  l-ft 

•  ••40 

O  ""» 


FIG.  153.  —  Sketch  showing  the  distribution  and  production  of  wells,  in  the 
Thrall  oil  field,  Texas.  Contour  lines  show  position  of  upper  surface  of  oil- 
bearing  rock  in  feet  below  sea  level.  (After  Udden  and  Bybee.) 


of  shale  and  clay,  with  gypsum,  calcite,  glauconite,  and  marcasite. 
The  oil-bearing  formation  is  a  porous,  soft  green  rock  found  in  the 

iUDDEN,  J.  A.,  and  BYBEE,  H.  P.  :  The  Thrall  Oil  Field.     Texas  Univ.  Bull. 
66,  1916. 


344  GEOLOGY  OF  PETROLEUM 

Taylor  marl  at  a  depth  of  about  850  feet.  It  is  brecciated  and 
highly  altered.  Larsen,1  who  examined  specimens  microscopi- 
cally, states  that  some  specimens  appear  to  be  a  fine-grained  tuff. 

The  top  of  the  petroliferous  body  is  arched  to  form  a  dome,  and 
the  oil  accumulation  is  related  to  the  dome. 

The  oil  is  of  low  specific  gravity  and  has  a  paraffin  base.  It  is 
heavier  but  in  many  respects  resembles  the  oil  of  the  Corsicana 
field  which  comes  from  a  sand  in  the  Taylor  marl. 

Many  of  the  wells  in  this  field  (Fig.  153)  produced  some  gas,  and 
the  gushing  of  the  wells  is  ascribed  to  gas  pressure.  The  oil 
deposits  paraffin  rapidly  in  pipes  and  casing,  so  that  wells  become 
plugged  with  it  and  cease  to  yield  until  treated. 

INITIAL  PRODUCTION  OF  SEVENTY  WELLS  IN  THE  THRALL  OIL  FIELD 


Production  (Barrels  per  Day) 

Number  of  Wells 

5,000  to  1,001  

7 

1,000  to  201  

15 

200  to  41 

22 

40  to  9  

19 

8  to  1 

7 

References  for  Texas  Fields 

ADAMS,  G.  I. :  Oil  and  Gas  Fields  of  Western  Interior  of  Northern  Texas 
Coal  Measures,  and  of  the  Upper  Cretaceous  and  Tertiary  of  the  Western  Gulf 
Coast.  U.  S.  Geol.  Survey  Bull.  184,  pp.  1-64,  1901. 

BEEDE,  J.  W. :  Notes  on  the  Structure  and  Oil  Showings  in  the  Red  Beds  of 
Coke  County,  Texas.  Am.  Assoc.  Pet.  Geol.  Bull.,  vol.  3,  pp.  117-123,  1919. 

BEEDE,  J.  W.,  and  WAITE,  V.  V. :  The  Geology  of  Runnels  County,  Texas. 
Univ.  Bull.  1816,  1918. 

DEUSSEN,  ALEXANDER:  Geology  and  Underground  Waters  of  the  South- 
eastern Part  of  the  Texas  Coastal  Plain.  U.  S.  Geol.  Survey  Water-Supply 
Paper  335,  pp.  1-365,  1914. 

DUMBLE,  E.  T. :  The  Occurrence  of  Petroleum  in  Eastern  Mexico  as  Con- 
trasted with  Those  in  Texas  and  Louisiana.  Am.  Inst.  Min.  Eng.  Bull.t 
August,  1915,  pp.  1623-38. 

ECKES,  C.  R. :  Description  of  Cullings  from  the  Duffer  Wells,  Ranger  Field. 
Am.  Assoc.  Pet.  Geol.  Bull,  vol.  3,  pp.  39-43,  1919. 

,  J.  A.,  and  BYBEE,  H.  P.:  Op.  cit.,  p.  39. 


MID-CONTINENT  FIELDS  345 

FENNEMAN,  N.  M. :  Oil  Fields  of  the  Texas-Louisiana  Gulf  Coastal  Plain. 
U.  S.  Geol.  Survey  Bull.  282,  pp.  1-146,  1906. 

FOHS,  JULIUS:  Geology  of  Texas  Oil  Fields.  Oil  and  Gas  Jour.  Suppl., 
May,  1919,  pp.  109-119. 

GIRTY,  G.  H. :  The  Bend  Formation  and  Its  Correlation.  Am.  Assoc.  Pet. 
Geol.  Bull ,  vol.  3,  pp.  71-81,  1919. 

GORDON,  C.  H. :  Geology  and  Underground  Waters  of  the  Wichita  Region, 
Texas.  U.  S.  Geol.  Survey  Water-Supply  Paper  317,  pp.  1-88,  1913. 

Geology   and   Underground   Waters   of   Northeastern   Texas. 

U.  S.  Geol.  Survey  Water-Supply  Paper  276,  pp.  1-78,  1911. 

GOULD,  C.  N. :  Geology  and  Water  Resources  of  the  Eastern  Portion  of  the 
Panhandle  of  Texas.  U.  S.  Geol.  Survey  Water-Supply  Paper  154,  pp.  1-64, 
1906. 

HARRIS,  G.  D. :  Oil  and  Gas  in  Louisiana,  with  a  Brief  Summary  of  Their 
Occurrence  in  Adjacent  States.  U.  S.  Geol.  Survey  Bull.  429,  pp.  1-192,  1910. 

HAYES,  C.  W.,  and  KENNEDY,  WILLIAM:  Oil  Fields  of  the  Texas-Louisiana 
Gulf  Coastal  Plain.  U.  S.  Geol.  Survey  Bull.  212,  pp.  1-174,  1903. 

HILL,  R.  T.:  Geology  of  Black  and  Grand  Prairies,  Texas.  U.  S.  Geol. 
Survey  Twenty-first  Ann.  Rept.,  part  7,  pp.  1-666,  1900. 

HILL,  R.  T ,  and  VAUGHAN,  T.  W  :  U.  S.  Geol.  Survey  Geol.  Atlas,  Austin 
folio  (No.  76),  1902. 

HOPKINS,  O.  B. :  The  Brennan  Salt  Dome,  Washington  and  Austin  Counties, 
Texas.  U.  S.  Geol.  Bull.  661,  pp.  271-280,  1918. 

The  Palestine  Salt  Dome,  Anderson  County,  Texas.     U.  S. 

Geol.  Survey  Bull.  661,  pp.  253-270,  1918. 

MATSON,  G.  C.,  and  HOPKINS,  O.  B.:  The  Corsicana  Oil  and  Gas  Field, 
Texas.  U.  S.  Geol.  Survey  Bull.  661,  pp.  211-252,  1918. 

MATTESON,  W.  G. :  A  Review  of  the  Development  of  the  New  Central  Texas 
Oil  Fields  During  1918.  Econ.  Geology,  vol.  14,  pp.  95-146,  1919. 

MOORE,  R.  C. :  The  Bend  Series  of  Central  Texas.  Am.  Assoc.  Pet.  Geol. 
Bull,  vol.  3,  pp.  216-241,  1919. 

PLUMMER,  F.  B. :  Preliminary  Paper  on  the  Stratigraphy  of  North-Central 
Texas.  Am.  Assoc.  Pet.  Geol.  Bull,  vol.  3,  pp.  132-150,  1919. 

PAIGE,  SIDNEY:  Mineral  Resources  of  the  Llano-Burnet  Region,  Texas. 
U.  S.  Geol.  Survey  Bull.  450,  pp.  1-103,  1911;  Geol.  Atlas,  folio  183,  1912. 

PHILLIPS,  W.  B. :  Oil  Prospects  in  Texas.  Oil  and  Gas  Jour.,  vol.  13,  p.  25, 
April  15,  1915. 

PRATT,  W.  E.:  Geologic  Structure  and  Producing  Areas  in  North  Texas 
Petroleum  Fields.  Am.  Assoc.  Pet.  Geol.  Bull,  vol.  3,  pp.  44-70,  1919. 

SELLARDS,  E,  H. :  Structural  Conditions  in  the  Oil  Fields  of  Bexar  County, 
Texas.  Am.  Assoc.  Pet.  Geol.  Bull,  vol.  3,  pp.  299-309, 1919. 

SHAW,  E.  W.,  MATSON,  G.  C.,  and  WEGEMANN,  C.  H.:  Natural  Gas  Re- 
sources of  Parts  of  Northern  Texas.  U.  S.  Geol.  Survey  Bull.  629,  pp.  1-126, 
1916. 

UDDEN,  J.  A.:  Oil-Bearing  Formations  in  Texas.  Am.  Assoc.  Pet.  Geol. 
Bull.,  vol.  3,  pp.  82-98,  1919. 

• Oil  in  an  Igneous  Rock.  Econ.  Geology,  vol.  10,  pp.  582-585, 

1915. 


346  GEOLOGY  OF  PETROLEUM 

UDDEN,  J.  A.:  Thrall  Oil  in  Serpentine.  Oil  and  Gas  Jour.,  vol  13,  p.  27, 
April  22,  1915. 

Subsurface  Geology  of  the  Oil  Districts  of  North-Central  Texas. 

Am.  Assoc.  Pet.  Geol.  Bull.,  vol.  3,  pp.  34-38,  1919. 

and   PHILLIPS,  D.  McN. :  Geology  of  the  Oil  and  Gas  Fields  of 

Wichita  and  Clay  Counties,  Texas.     Texas  Univ.  Bull.  246,  p.  16, 1912. 

BAKER,  C.  L.,  and  Boss,  EMIL:  Review  of  the  Geology  of 

Texas.    Texas  Univ.  Bull.  44,  with  large  map  of  Texas,  1916. 

VAUGHAN,  T.  W. :  U.  S.  Geol.  Survey  Geol.  Atlas,  Uvalde  folio  (No.  64),  1900. 
WEGEMANN,  C.  H.:  A  Reconnaissance  for  Oil  Near  Quanah,  Hardeman 
County,  Texas.     U.  S.  Geol.  Survey  Bull  621,  pp.  109-115,  1915. 

A  Reconnaissance  in  Palo  Pinto  County,  Texas,  with  Special 

Reference  to  Oil  and  Gas.     U.  S.  Geol.  Survey  Bull.  621,  pp.  51-59, 1915. 

NORTHWESTERN  LOUISIANA  AND  NORTHEASTERN  TEXAS 

General  Features. — Northwestern  Louisiana  and  northeastern 
Texas  are  covered  with  Tertiary  and  Quaternary  deposits,  which 
extend  northward  on  both  sides  of  the  Mississippi  River  to  Cairo, 
Illinois.  The  country  is  flat,  and  rock  exposures  are  rare  over  con- 
siderable parts  of  the  area.  The  rocks  at  the  surface  generally  dip 
at  low  angles  away  from  the  older  rocks  that  occur  farther  north. 
There  is  a  gentle  dip  toward  the  Mississippi  River,  which  is  prob- 
ably parallel  to  and  not  far  from  the  axis  of  a  gentle  syncline  or 
broad  fluting  on  the  monocline  that  dips  south  at  a  low  angle. 
Superimposed  on  the  monocline  of  the  Mississippi  embayment 
(Fig.  154)  are  long  and  relatively  narrow  zones  of  deformation 
marked  by  faulting  or  by  folding.  These  zones  probably  extend 
for  hundreds  of  miles,  although  they  are  not  continuously  exposed. 

One  of  these  zones  of  deformation  is  the  Red  River  fault  zone 
(Fig.  155).  This  zone,  as  stated  by  Hill,1  consists  principally  of 
two  nearly  parallel  major  fault  lines  extending  S.  60°  E.,  or  in  a 
direction  perpendicular  to  that  of  the  Balcones  fault  zone.  Their 
downthrows  are  in  opposite  directions,  and  between  them  is  a  strip 
or  block  of  uplifted  strata,  as  seen  between  Red  River  north  of 
Denison  and  Cook  Spring,  to  the  south.  The  northern  of  these 
faults  follows  Red  River  from  Marshalls  Bluff,  near  Preston  (old), 
to  the  northeast  corner  of  Grayson  County.  Its  downthrow  is 
north,  and  it  is  occupied  by  Red  River  north  of  Denison.  On  the 
north  side  of  Red  River  the  beds  from  the  Woodbine  formation 
downward,  are  lowered.  They  face  the  Antlers  sand  and  Goodland 

1HiLL,  R.  T. :  Geography  and  Geology  of  Black  and  Grand  Prairies,  Texas. 
U.  S.  Geol.  Survey  Twenty-first  Ann.  Rept.,  part  7,  p.  384,  1901. 


MID-CONTINENT  FIELDS 


347 


limestone  on  the  south.     The  downthrow  at  Preston  is  about  626 
feet,  and  north  of  Denison  it  is  617  feet. 

Nearly  parallel  to  this  fault  and  from  5  to  7  miles  south  of  it  is 
the  Cook  Spring  fault.  (See  Fig.  155.)  This  fault  line  passes 
from  the  north  edge  of  Grayson  County  south  of  east  near  Potts- 


Scale 
too 


200  miles 


Quaternary  fe'tiary  with 


LEGEND 


Upper 


Lower 
Cretaceous 


Paleozoic 


FIG.  154. — Map   showing   geology   of  the   lower   Mississippi   valley.  (After 

Veatch.) 


boro  and  through  Cook  Spring.  Its  downthrow  consists  of  several 
steps  to  the  south  and  amounts  to  about  200  feet  near  Pottsboro. 
At  1H  miles  northeast  of  Pottsboro  the  Dexter  sands  abruptly 


348  GEOLOGY  OF  PETROLEUM 

terminate  and  the  Eagle  Ford  clays  are  faulted  down  opposite  the 
Fort  Worth  limestone  and  the  basal  Denison  beds.  In  the 
northern  part  of  Grayson  County l  the  rocks  are  folded  along  an  anti- 
cline having  a  generally  similar  strike.  Possibly  anticlines  in  Cotton 
and  Jefferson  Counties,  Oklahoma,  and  the  Devol  anticline  in  the 
Grandfield  area  may  belong  to  the  same  zone  of  deformation.2 

In  northwestern  Louisiana  the  Red  River  zone  of  deformation  is 
probably  represented  by  a  sharp  flexure  that  dips  north,  away  from 
the  Sabine  uplift.  As  mapped  by  Veatch  this  zone  extends  to  the 
Mississippi  River. 

The  Angelina  flexure  extends  from  Angelina  County,  Texas, 
northeastward  into  Louisiana  and  possibly  to  the  Mississippi 
River.  Along  the  flexure  the  rocks  dip  to  the  southeast  at  a  high 
angle.  Between  the  Red  River  zone  of  deformation  and  the 
Angelina  flexure  lies  a  great,  broad  dome — the  Sabine  uplift. 
From  this  dome  the  rocks  dip  northeast  along  the  Red  River  zone 
of  deformation,  east  to  the  Mississippi  River,  southeast  along  the 
Angelina  flexure,  and  west  in  eastern  Texas. 

In  this  region  deformation  has  taken  place  in  late  geologic  time. 
According  to  Veatch,  shoals  on  the  Sabine  River  and  a  ridge 
across  Angelina  River  are  due  to  this  flexure.3  In  the  Wilcox 
formation  of  the  Eocene,  the  rocks  locally  dip  10°  or  more. 

Contour  maps  of  the  structure  of  the  Sabine  uplift,  based  on 
well  logs,  show  that  the  dome  has  an  undulating  crest.  Three 
anticlinal  axes  are  noteworthy.  These  are  approximately  parallel 
and  strike  northeast.  On  the  north  one  are  the  oil  fields  of  Caddo 
Lake.  The  central  axis  lies  near  Shreveport  and  extends  north- 
eastward, passing  through  the  Homer  field.  South  of  this  is  a 
third  axis  which  is  developed  in  the  De  Soto-Red  River  field.  It 
practically  coincides  with  the  Gusher  Bend  fault  of  that  field. 
High  points  along  the  crests  of  these  folds  are  essentially  in  line, 

^TEPHENSON,  L.  W. :  A  Contribution  to  the  Geology  of  Northeastern  Texas 
and  Southern  Oklahoma.  U.  S.  Geol.  Survey  Prof.  Paper  120,  pp.  129-163, 
1919. 

*MuNN,  M.  J.:  Reconnaissance  of  the  Grandfield  District,  Oklahoma. 
U.  S.  Geol.  Survey  Bull  547,  pp.  1-85,  1914. 

WEGEMANN,  C.  H. :  Anticlinal  Structure  in  Parts  of  Cotton  and  Jefferson 
Counties,  Oklahoma.  U.  S.  Geol.  Survey  Bull  602,  pp.  1-108, 1915. 

•VEATCH,  A.  C. :  Geology  and  Underground  Water  Resources  of  Northern 
Louisiana  and  Southern  Arkansas.  U.  S.  Geol.  Survey  Prof.  Paper  46,  p.  68, 
1906. 


MID-CONTINENT  FIELDS 


349 


suggesting  a  second  series  of  folds  striking  northwestward  across 
the  axes  of  the  northeast  folds. 


FIG.  155. — Map  showing  probable  structural  lines  in  Mississippi  embayment 
region.   (After  Harris.) 


350  GEOLOGY  OF  PETROLEUM 

The  fields  on  the  Sabine  uplift  that  yield  oil  or  gas  or  both 
include  the  Caddo,  Shreveport,  De  Soto-Red  River  (Bull  Bayou), 
Elm  Grove,  Pelican,  Homer,  Monroe,  and  others.  (See  Fig.  156.) 
The  Caddo  field  yields  gas  and  heavy  oil  from  the  Nacatoch  sand 
and  also  from  the  Annona  chalk  of  the  Austin.  It  yields  light  oil 
(38°  B.)  from  the  Blossom  sand  member  of  the  Eagle  Ford  clay 
and  from  the  Woodbine  sand.  The  Shreveport  gas  field  yields  gas 
from  the  Nacatoch.  The  Red  River-De  Soto  gas  field  yields  gas 
from  the  Nacatoch  and  much  oil  from  the  deeper  sands  near  the 
bottom  of  the  Upper  Cretaceous.  The  Homer  field  probably 
yields  oil  from  the  same  strata  or  from  the  Blossom.  The  Pelican 
field  yields  gas  from  the  Nacatoch  and  oil  from  the  Blossom. 
About  100  miles  east  of  Shreveport,  at  Monroe,  Ouachita  Parish, 


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FIG.  156. — Sketch  map  showing  oil  and  gas  fields  in  northern  Louisiana  and 
northeastern  Texas.  Bethany,  Shreveport,  Elm  Grove  and  Monroe  are  gas 
fields.  Caddo,  Homer,  Bull  Bayou  and  Pelican  are  oil  fields. 

Louisiana,  a  large  gas  field  has  recently  been  developed  on  a  great 
anticline  or  dome.  Practically  all  the  fields  yield  gasoline,  recov- 
ered from  gas. 

The  Nacatoch  sand  is  porous  over  wide  areas  and  is  gas-bearing 
in  all  the  large  fields  in  northwestern  Louisiana,  as  well  as  in  the 
Balcones  fault  region,  Texas.  Its  thickness  ranges  from  50  to  150 
feet  and  averages  125  feet. 

The  oil  in  the  deeper  sands  of  the  northern  Louisiana  fields  is 
associated  with  much  gas.  Some  of  the  wells  are  large  gushers. 
Recently  wells  yielding  10,000  barrels  a  day  have  been  brought  in 


MID-CONTINENT  FIELDS 


351 


near  Homer,  on  the  east  extension 
of  the  field.  Salt  water  is  found  be- 
low the  oil. 

A  section  across  this  region  is 
shown  in  Fig.  157. 

Caddo  Field.  —  The  Caddo  oil  and 
gas  field  is  northwest  of  Shreveport, 
mainly  in  Caddo  Parish,  Louisiana, 
and  extends  a  short  distance  west- 
ward into  Texas.  The  producing 
wells  occupy  an  area  extending 
northwestward  from  Mooringsport, 
Louisiana,  for  about  12  miles,  and 
a  long,  narrow  belt  extending  nearly 
10  miles  northeastward  from  the 
north  end  of  the  main  field.  Natural 
gas  has  been  known  at  Shreveport 
for  more  than  a  quarter  of  a  century, 
though  its  exploitation  was  not 
begun  until  1912,  after  large  gas- 
producing  areas  had  been  developed 
in  the  northern  part  of  Caddo 
Parish.1  The  area  south,  near  the 
city  of  Shreveport,  produces  gas 
and  some  oil. 

The  country  is  flat  with  small  hills 
rising  a  few  feet  above  the  surface. 
These  hills,  according  to  Matson, 
are  not  structural  features,  but  are 
probably  the  work  of  ants. 


,  G.  D.  :  Oil  and  Gas  in  Louisi- 
ana. U.  S.  Geol.  Survey  Bull.  429,  1910. 

MATSON,  G.  C.  :  The  Caddo  Oil  and  Gas 
Field,  Louisiana  and  Texas.  U.  S.  Geol. 
Survey  Bull.  619,  pp.  1-62,  1916. 

VEATCH,  A.  C.:  Geology  and  Under- 
ground Waters  of  Northern  Louisiana 
and  Southern  Arkansas.  U.  S.  Geol.  Sur- 
vey Prof.  Paper  46,  1906, 


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352 


GEOLOGY  OF  PETROLEUM 


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MID-CONTINENT  FIELDS  355 

Gas  seeps  have  been  noted  in  water  pools  and  in  Caddo  Lake, 
and  these  led  to  drilling.  Oil  or  gas  or  both  are  found  in  the 
Nacatoch  sand,  the  Annona  chalk,  the  Blossom  sand  member  of 
the  Eagle  Ford  clay,  and  the  Woodbine  sand.  The  oil  is  of  high 
grade,  some  of  it  38°  B.  or  higher.  Some  of  the  oil  issues  in 
gushers. 

In  the  Caddo  field  shallow  anticlines  and  synclines  are  developed 
on  the  Sabine  uplift,  and  smaller  folds  are  superimposed  on  these. 
The  oil  and  gas  are  concentrated  in  the  elevated  portions  of  the 
folds. 

De  Soto-Red  River  Field.— The  De  Soto-Red  River  field  is  about 
50  miles  south  of  the  Caddo  field.  The  rocks  are  of  Eocene  and 
Upper  Cretaceous  age.  The  formations  present  at  Caddo  are 
noted  also  in  this  field. 1  The  principal  oil  sand  is  below  the  Browns- 
town  marl,  at  depths  between  2,450  and  2,750  feet.  Gas  and 
heavy  oil  are  found  in  the  Nacatoch  sand,  and  light  oil  in  the  Blos- 
som sand  member  of  the  Eagle  Ford  clay,  which  lies  about  1,600 
feet  below  the  Nacatoch.  It  is  not  certain  whether  this  is  the 
Blossom  or  the  Woodbine  sand.  It  has  been  suggested  that  Jt 
may  be  older  than  the  Woodbine. 

A  fault  with  a  throw  of  200  to  225  feet  strikes  northeast  near  the 
largest  anticline.  This  is  known  as  the  Gusher  Bend  fault,  from 
its  occurrence  near  a  bend  in  Red  River  where  on  a  small  dome 
numerous  wells  with  large  flow  were  drilled. 

Pelican  Field.— The  Pelican  field  is  about  50  miles  south  of 
Shreveport,  in  the  northern  part  of  Sabine  Parish,  Louisiana.  The 
section  is  similar  to  that  of  the  De  Soto-Red  River  field,  and  the 
structure  is  domatic. 

The  Nacatoch  sand  is  reached  at  a  depth  below  sea  level  ranging 
from  900  feet  in  the  northern  part  of  the  field  to  about  1,350  feet 
in  the  southern  part.  In  this  area  it  consists  largely  of  hard  sandy 
shale  and  sandstone  with  only  a  relatively  small  amount  of  loose 
sand.  It  has  yielded  gas  and  heavy  oil. 

The  principal  productive  oil  sand  in  this  field  is  the  Blossom 
sand,  which  occurs  at  a  depth  ranging  from  2,800  feet  in  the 
northern  part  of  the  field  to  3,200  feet  in  the  southern  part. 

WATSON,  G.  C.,  and  HOPKINS,  O.  B.:  The  De  Soto-Red  River  Oil  and 
Gas  Field,  Louisiana.  U.  S.  Geol.  Survey  Bull  681,  pp.  101-140,  1918. 


356 


GEOLOGY  OF  PETROLEUM 


FORMATIONS  OF  GULF  SERIES  (UPPER  CRETACEOUS)  IN  DE  SOTO-RED  RIVER 
OIL  AND  GAS  FIELD,  LOUISIANA 

(After  Matson  and  Hopkins) 


Formation 

Character 

Oil  or  Gas 

Range  in  Depth 

Arkadelphia  clay. 

Stiff,  gummy  clay, 
with  some  sandy 
layers  in  lower 
part. 

Nacotch  sand. 

Sand,  with  some 
layers  of  clay  and 
hard  sandstone. 

Prominent  gas 
sand. 

Top  at  725-975 
feet. 

Marlbrook  marl. 

Shale  or  marl  above; 
white  chalk  below. 

Some  oil,  suppos- 
edly derived 
from  lower  for- 
mations through 
faults. 

Top  at  850-1  ,050 
feet. 

Annona  chalk. 

Chalk. 

Brownstown  marl  . 

Probably  marl  and 
chalk  above;  shale 
and  sandy  shale, 
with  some  sand, 
below. 

Showings  of  oil 
and  gas  below 
base  of  chalk. 

Eagle  Ford  shale. 

Shales,  sands,  and 
probably  lime- 
stone beds. 

Principal  oil  sand 
of  field;  also 
deep  gas  sand.0 

Oil  sand  at  2,450- 
2  ,550  feet;  deep 
gas  sand  at 
2,650-2,750feet. 

Woodbine  sand. 

Not  definitely  recog- 
stone  beds. 

'Exact  correlation  uncertain;  may  be  older  than  indicated. 


Stephens ville,  Arkansas. — A  fifty-barrel  well  was  brought  in 
near  Stephens  ville,  Ouachita  County,  Arkansas,  in  1920.  The 
oil  is  in  a  sand  of  the  Upper  Cretaceous,  probably  the  Woodbine 
or  the  Blossom  sand. 


MID-CONTINENT  FIELDS  357 

References  for  Louisiana  Fields 

BATES,  MOWRY:  A  Concrete  Example  of  the  Use  of  Well  Logs.  Am.  Inst. 
Min.  Eng.  Bull.  137,  1918. 

BERRY,  E.  W. :  The  Lower  Eocene  Floras  of  Southeastern  North  America. 
U.  S.  Geol.  Survey  Prof.  Paper  91,  pp.  1-481,  1916. 

DUMBLE,  E.  T. :  The  Age  and  Manner  of  Formation  of  Petroleum  Deposits. 
Am.  Inst.  Min.  Eng.  Trans.,  vol.  48,  pp.  54-532,  1915;  Am.  Inst.  Min.  Eng. 
Bull,  1915,  pp.  1623-1638. 

GARDNER,  J.  H. :  The  Mid-Continent  Oil  Fields.  Geol.  Soc.  America  Bull, 
vol  28,  pp.  709-714,  1917. 

HARRIS,  G.  D.:  Oil  and  Gas  in  Louisiana.  U.  S.  Geol.  Survey  Bull.  429, 
pp.  1-192,  1910. 

HARRIS,  G.  D.,  PERRINE,  I.,  and  HOPPER,  W.  E. :  Oil  and  Gas  in  North- 
western Louisiana,  with  Special  Reference  to  the  Caddo  Field.  Louisiana 
Geol.  Survey  Bull.  8,  pp.  1-48,  1909. 

LUCAS,  A.  F. :  The  Possible  Existence  of  Deep-seated  Oil  Deposits  on  the 
Gulf  Coast.  Am.  Inst.  Min.  Eng.  Bull.  139,  1918. 

MATSON,  G.  C. :  The  Caddo  Oil  and  Gas  Field,  Louisiana  and  Texas.  U.  S. 
Geol.  Survey  Bull.  619,  pp.  1-62,  1916. 

MATSON,  G.  C.,  and  HOPKINS,  O.  B.:  The  De  Soto-Red  River  Oil  and  Gas 
Field,  Louisiana.  U.  S.  Geol.  Survey  Bull.  661,  pp.  101-140,  1918. 

SOMERS,  R.  E. :  Louisiana  Oil  and  Gas  Fields.  Oil  and  Gas  Jour.  Suppl., 
May,  1919,  pp.  125-129. 

VAUGHAN,  T.  W. :  A  Brief  Contribution  to  the  Geology  and  Paleontology  of 
Northwestern  Louisiana.  U.  S.  Geol.  Survey  Bull.  142,  pp.  1-65, 1896. 

VEATCH,  A.  C. :  Geology  and  Underground  Water  Resources  of  Northern 
Louisiana  and  Southern  Arkansas.  U.  S.  Geol.  Survey  Prof.  Paper  46,  pp. 
1-422,  1906. 


CHAPTER  XVIII 
PROSPECTS   IN  MISSISSIPPI,  ALABAMA  AND  GEORGIA 


Mississippi. — The  Vicksburg-Jackson  area1  of  Mississippi  lies 
east  of  the  Louisiana  fields.  The  area  is  no  more  diversified 
topographically  than  other  areas  in  the  Coastal  Plain  where  the 
maximum  relief  does  not  exceed  300  feet,  the  maximum  elevation 
above  sea  level  is  not  greater  than  500  feet,  and  there  are  only 
slight  differences  in  hardness  of  rocks.  The  main  features  are 
the  broad,  flat  valleys  that  cross  the  region  in  general  from  north  to 
south  and  the  interstream  tracts,  which  in  the  western  part  of  the 
area  are  much  dissected  and  have  angular  topographic  features 
and  in  the  eastern  part  are  flat  or  rolling  plains. 

The  city  of  Jackson  is  near  the  center  of  a  broad,  gentle  fold, 
which  shows  a  domelike  arch  in  cross-section  from  northwest  to 
southeast  and  a  terrace-like  form  from  northeast  to  southwest. 
Near  the  southwestern  and  southern  parts  of  the  anticline  the  dips 
are  as  much  as  60  to  70  feet  to  the  mile;  in  the  northwestern  and 
southwestern  parts  they  are  30  feet  or  less  to  the  mile.  The 
northern  extent  of  this  fold  has  not  been  determined.  No  oil  seeps 
are  reported. 

The  presence  of  a  porous  stratum  is  probable,  as  sands  approxi- 
mately the  equivalent  of  those  that  are  productive  in  Louisiana, 
the  Ripley  and  Tuscaloosa,  are  known  to  dip  under  this  region, 
although  their  depth  and  nature  in  the  Mississippi  field  are  im- 
perfectly known. 

All  the  rocks  of  the  Vicksburg-Jackson  region  are  sedimentary 
in  origin  and  relatively  young,  the  exposed  rocks  ranging  in  age 
from  Claiborne  (Eocene)  to  Recent,  as  shown  in  the  upper  part  of 
the  following  table.  The  formations  below  the  Claiborne  are 
below  drainage  level. 

HOPKINS,  O.  B.:  Structure  of  the  Vicksburg-Jackson  Area,  Mississippi 
U.  S.  Geol.  Survey  Bull.  641,  pp.  93-120,  1917. 

CRIDER,  A.  F. :  Geology  and  Mineral  Resources  of  Mississippi.  U.  S.  Geol. 
Survey  Bull.  283,  1906. 

CRIDER,  A.  F. :  Oil  and  Gas  Possibilities  in  Mississippi.  Southwestern 
Assoc.  Pet.  Geol.  Bull.  1,  pp.  152-155,  1917. 

358 


PROSPECTS  IN  MISS.,  ALA.,  AND  GEORGIA 


SECTION  OF  FORMATIONS  IN  VICKSBURG- JACKSON  AREA 
(After  Hopkins) 


System 

Series 

Group  or 
Formation 

Thickness 

Character 

Recent. 

Alluvium. 

Feet 

Sand,   clay,  and  silt  along  present 

streams. 

Quaternary  . 

^oess    and    yel- 
low loam. 

0-100 

Clay,  fine  gray  to  buff,  calcareous, 
and  yellow  to  brown  loam. 

Alluvial  terrace 
deposits. 

0-50 

Sand,  gravel,  and  clay. 

Pliocene. 

Sand  and  gravel. 

0-50 

Terrace  sand  and  gravel. 

Catahoula  sand- 
stone. 

0-75 

Unconsolidated  sands,  sandstones, 
gray  siliceous  clay,  and  some  lig- 
nitic  material. 

Vicksburg  lime- 
stone. 

80-130 

Marl  and  clay  above,  containing 
marine  shells;  limestone  and  im- 
pure limestone  and  marl  below. 

Tertiary. 

Jackson   forma- 
tion. 

250-500  (?) 

Sand  above,  cross-bedded,  green  to 
yellow  nonfossiliferous;  gray  clay 
weathering  black  below  and  sand 
beds  at  base.  Both  clay  and  sand 
beds  contain  marine  shells. 

Eocene. 

C  1  a  i  b  o  r  n  e 
group. 

500-1  ,000 

Marls,  sands,  lignitic  clays,  and  lig- 
nite above;  quartzite,  clay  stone, 
and  marl  below. 

Wilcox  group. 

850-1  ,500  (?) 

Lignitic  clays  and  sands,  with  sand 
predominating  in  middle  part. 

Midway  group  . 

100-300 

Clay,  dark  gray  to  black,  and  mica- 
ceous sandstone,  with  hard  lime- 
stone and  sandy  marl  below. 

Ripley   forma- 
•  tion. 

50-300 

Sands,  clays,  marls,  and  impure  lime- 
stones of  marine  origin. 

Cretaceous. 

Upper. 

Selma  chalk. 

600-1,000 

Chalky  limestone  with  argillaceous 
and  sandy  beds. 

Eutaw      forma- 
tion. 

300-400 

Sands,  massive  and  cross-bedded. 

Tuscaloosa   for- 
mation. 

100-300 

Irregularly  bedded  sands,  clays,  and 
gravels,  containing  clay  and  lig- 
nitic layers  at  top. 

360  GEOLOGY  OF  PETROLEUM 

GENERALIZED  GEOLOGIC  SECTION  OP  WESTERN  ALABAMA 


Geologic  Age 

Group 

Formation 

Thick- 
ness 

Character 

Pliocene- 
Pleistocene. 

Lafayette. 

Feet 
25 

Gravel,  sands,  clays. 

Lower  Mio- 
cene. 

Grand  Gulf. 

50 

Soft    sandstones    and 
clays. 

Lower  Oligo- 
cene. 

St.  Stephens  lime- 
stone. 

300 

Unusually    soft    lime- 
stone, easily  cut  with 
saw. 

Eocene. 

Claiborne. 

Gosport  greensand. 
Lisbon. 

Tallahatta  buhr- 
stone. 

30 
115 

400 

Glauconitic  sands. 
Calcareous   clays   and 
sandy  clay. 
Aluminous  sandstones 
and  siliceous  clays. 

Chickasaw 
(Wilcox). 

Hatchetigbee. 
Bashi. 
Tuscahoma. 
Nanafalia. 

175 
80 
140 
200 

Sandy  clays  and  cross- 
bedded  sands. 
Sands  and  clays.    Fos- 
siliferous  greensand. 
Gray  and  yellow  cross- 
bedded  sands. 
Siliceous  clays. 

Midway. 

Naheola. 

Sucarnochee  clay. 
Clayton. 

150 

100 
50 

Gray  sandy  clays. 
Glauconitic  clays. 
Dark-brown  clay. 
Impure  limestone. 

Upper  Cre- 
taceous. 

Ripley. 
Selma  chalk. 
Eutaw  sands. 
Tuscaloosa. 

300 
950 
500 
1,000 

Calcareous     and    sili- 
ceous sands. 
Argillaceous  lime- 
stones. 
Glauconitic  sands, 
cross-bedded. 
Irregular  bedded  sands, 
clays,  and  gravels. 

Alabama. — Gas  and  some  oil  have  been  discovered  in  the  Penn- 
sylvanian  series  in  northwestern  Alabama  (see  p.  247),  but  the 


PROSPECTS  IN  MISS.,  ALA.  AND  GEORGIA      361 

production  has  not  been  large.  In  southern  Alabama,  according 
to  Hager,1  there  are  several  localities  where  oil  may  possibly  be 
found  in  the  Cretaceous  beds. 


l-Hatchefigbtt 
1-Jackson 
3-6entva 
A-  Gordon 


FIG.  158.  —  Index  map  of  Alabama  showing  position  of  anticlines  in  the 
southern  part  of  the  State.   (After  Hager.) 


The  Hatchetigbeefold  (see  Fig.  158),  recently  described  by  Hop- 
^AGER,  DORSEY:  Possible  Oil  and  Gas  Fields  in  the  Cretaceous  Beds  of 
Alabama.     Am.  Inst.  Min.  Eng.  Bull.  134,  pp.  469-476,  1918. 


362  GEOLOGY  OF  PETROLEUM 

kins,1  also  by  Hager,  runs  in  a  general  southeasterly  direction 
through  portions  of  Choctaw,  Clarke  and  Washington  Counties 
and  is  about  20  miles  long  and  4  to  5  miles  wide.  Along  the  axis  the 
Hatchetigbee  formation  crops  out.  This  formation  is  about  550 
feet  lower  stratigraphically  than  the  St.  Stephens  limestone,  which 
crops  out  on  all  sides  of  the  fold.  The  reversal  is  not  much  less 
than  500  feet.  The  pitch  of  the  strata  away  from  the  axis  of  the 
anticline  ranges  from  1°  to  nearly  2°. 

The  Jackson  anticline  is  in  all  probability  a  part  of  the  same  fold 
as  the  Hatchetigbee  anticline.  Along  the  axis  of  the  Jackson  anti- 
cline, rocks  of  the  Claiborne  group  are  exposed,  and  the  reversal  is 
not  much  less  than  that  of  the  Hatchetigbee  anticline,  from  which 
this  fold  is  separated  by  a  saddle. 

Toward  the  east,  according  to  Hager,  no  marked  folding  is  noted 
until  Geneva  County  is  reached.  In  an  area  near  Geneva,  cover- 
ing possibly  20  square  miles,  the  Claiborne  rocks  are  exposed  at 
the  surface,  with  the  St.  Stephens  limestone  surrounding  them. 
The  reversal  on  this  fold  is  probably  more  than  100  feet.  In  this 
area  exposures  are  meager,  owing  to  the  covering  of  the  Grand 
Gulf  and  Lafayette  formations. 

East  of  Geneva,  near  Gordon,  there  is  another  anticlinal  fold, 
on  the  Georgia  State  line.  It  has  a  reversal  of  40  feet  and  covers 
10  square  miles. 

The  formations  that  are  regarded  by  Hager  as  possible  sources 
of  the  oil  or  gas  are  the  Ripley,  the  Eutaw  (Tombigbee  sand),  and 
the  Tuscaloosa  (Woodbine  sand). 

A  well  on  the  Hatchetigbee  anticline  is  reported  to  have  had 
showings  of  gas  at  750  and  1,500  feet  and  of  oil  at  2,250  feet.  The 
750-foot  gas  horizon  is  probably  in  the  Ripley  formation,  and  the 
1,500-foot  horizon  is  in  the  Selma  chalk.  The  oil  at  2,250  feet  is 
below  the  Selma  chalk  and  probably  in  the  Eutaw  sands. 2 

Georgia. — A  seep  of  petroleum  was  reported  to  be  found  in  1919 
about  1  mile'  south  of  Scotland,  Telfair  County,  Georgia.3  The 

HOPKINS,  O.  B. :  Oil  and  Gas  Possibilities  of  the  Hatchetigbee  Anticline, 
Alabama.  U.  S.  Geol.  Survey  Bull.  661,  pp.  281-313,  1918. 

2HAGER,  DORSET:  Op.  cit.,  p.  475. 

SVEATCH,  OTTO,  and  STEPHENSON,  L.  W.:  Preliminary  Report  on  the 
Geology  of  the  Coastal  Plain  of  Georgia.  Georgia  Geol.  Survey  Bull.  26, 
pp.  60-61,  1911. 

HULL,  J.  P.  D.,  and  TEAS,  L.  P.:  Oil  Prospect  Near  Scotland,  Telfair 
County,  Georgia.  Georgia  Geol.  Survey,  pp.  3-5,  1919. 


PROSPECTS  IN  MISS.,  ALA.  AND  GEORGIA      363 


surface  deposits  throughout  the  interstream  areas  in  this  region 
consist  of  100  feet  or  less  of  irregularly  bedded  sandy  clays  and 
sands  with  subordinate  interbedded  layers  of  argillaceous  sand- 
stone. They  are  under- 
lain by  100  feet  or 
more  of  soft  sandy 
clays  and  sands,  in 
part  water-bearing, 
with  interbedded  thin 
layers  of  sandstone 
and  quart zite  that  be- 
long to  the  Alum  Bluff 
formation.  The  Alum 
Bluff  formation  is  un- 
derlain by  500  feet  or 
more  of  limestone  with 
interbedded  layers  of 
calcareous  sandstone 
and  marl,  which  prob- 
ably represent  in 
descending  order  the 
Chattahoochee  and 
Vicksburg  formations 
of  the  Oligocene  and 
perhaps  the  Jackson 
formation  of  the  Eo- 
cene. These  forma- 
tions contain  water- 
bearing beds.  Beneath 
the  limestones  are 
sediments  of  Eocene 
and  Cretaceous  age, 
which  probably  have 
an  aggregate  thickness 
of  1,500  feet  or  more 
and  which  rest  upon  a 
basement  of  ancient 
crystalline  rocks. 
These  also  contain  important  water-bearing  beds. 

The  dip  of  the  beds  is  southeastward  and  increases  with  the  age 


364  GEOLOGY  OF  PETROLEUM 

of  the  beds  from  4  to  5  feet  to  about  30  feet  to  the  mile.  The 
general  stratigraphic  relations  of  the  formations  are  shown  in 
Fig.  159. 

Examination  of  the  underlying  rocks  where  they  come  to  the 
surface  about  75  miles  north  of  Scotland  shows  them  to  be  largely 
of  marine  origin,  with  remnants  of  plant  and  animal  life.  These 
rocks  belong  to  the  Cretaceous  system,  which  is  oil-bearing  in 
Louisiana  and  Texas. 

It  is  not  yet  determined  whether  there  is  any  favorable  structure 
in  the  area. 


CHAPTER  XIX 
GULF  COAST  FIELDS  OF  TEXAS  AND  LOUISIANA 

Eastern  Texas  and  Louisiana  are  underlain  by  Mesozoic  and 
Cenozoic  rocks,  which  crop  out  as  broad  belts  in  which  the  younger 
rocks  lie  successively  nearer  the  sea.  The  younger  beds  extend 
farther  north  in  the  region  of  the  Mississippi  River  than  east  or 
west  of  it.  Structurally  the  region  has  been  characterized  as  a 
gently  pitching  trough  with  its  axis  lying  along  the  river.  The 
beds  in  general  dip  at  very  low  angles,  though  locally  they  are 
sharply  flexed.1 

The  country  is  approximately  flat,  and  details  of  structure  are 
derived  principally  from  drill  holes.  At  many  places  low  mounds 
or  hills  rise  above  the  generally  level  plain.  On  some  of  these 
there  are  small  lakes  from  which  gas  bubbles  escape.  Sulphur, 
sulphur  dioxide,  sulphuric  acid,  saline  water,  gas,  oil,  asphalt,  or 
"paraffin  dirt"  are  sought  for  as  evidences  of  oil-bearing  areas. 
These  indications  are  found  also  at  some  places  where  there  is  no 
mound  or  rise  of  the  land.  Drilling  has  shown  that  cores  of  salt 
with  petroliferous  beds  underlie  many  of  the  mounds  or  the  other 
places  where  one  or  more  of  the  indications  noted  above  are  pres- 
ent. The  distribution  of  the  salt  domes  is  shown  by  Fig.  160. 
A  cross-section  of  a  dome  is  shown  by  Fig.  42,  p.  136.  Some  of  them 
are  described  below. 

At  Spindletop,  in  southern  Texas,  about  3  miles  south  of  Beau- 

^ARRIS,  G.  D. :  Oil  and  Gas  in  Louisiana,  with  a  Brief  Summary  of  Their 
Occurrence  in  Adjacent  States.  U.  S.  Geol.  Survey  Bull.  429,  1910. 

FENNEMAN,  N.  M.:  Oil  Fields  of  Texas  and  Louisiana  Gulf  Coastal  Plain. 
U.  S.  Geol.  Survey  Bull  282,  1906. 

DEUSSEN,  ALEXANDER:  Geology  and  Underground  Waters  of  the  South- 
eastern Part  of  the  Texas  Coastal  Plain.  U.  S.  Geol.  Survey  Water-Supply 
Paper  335,  1914. 

VEATCH,  A.  C.:  Geology  and  Underground  Water  Resources  of  Northern 
Louisiana  and  Southern  Arkansas.  U  S.  Geol.  Survey  Prof.  Paper  46,  1906. 

HAYES,  C.  W.,  and  KENNEDY,  WILLIAM:  Oil  Fields  of  the  Texas-Louisiana 
Gulf  Coastal  Plain.  U.  S.  Geol.  Survey  Butt.  212,  1903. 

KENNEDY,  WILLIAM  :  Coastal  Salt  Domes.  Southwestern  Assoc.  Pet.  Geol, 
Bull,  vol.  1,  pp.  34-59,  1917. 

365 


366 


GEOLOGY  OF  PETROLEUM 


CENOZOIC  DEPOSITS  OF  THE  TEXAS  COASTAL  PLAIN 
(After  Deussen) 


Sys- 
tern 

Series 

Formation 

Thick- 
ness 

Lithology  and  Characteristic  Fossils 

Feet 

Fluviatile  deposits,    consisting   of  brown,    red,    or 

black  sandy  clay  or  silt  of  the  low,  overflow  ter- 

races of  the  streams;  flood-plain  materials,  includ- 

Recent. 

0-50 

ing     sand    and    gravel    bars. 

Recent    buffalo 

bones,    etc.     Seaward,    these 

fluvatile    deposits 

grade  into  interstream  deposits  consisting  of  yel- 

low and  blue  clays  and  yellow  wave-formed  sand, 

sand  and  shell  beaches,  bars,  and  barriers,  carry- 

ing Rangia  cuneata  and  other  fossils. 

Blue,  calcareous  clay,  with  nu- 

merous lime  concretions  about 

1    inch    through.     Lenses    of 

Beaumont  clay. 

800 

sand    and    sandy    clay.     The 

max. 

clays    carry    Rangia    cuneata, 

Farther  inland  the 

etc.;  embedded  logs  are  com- 

Lissie gravel  and 

mon. 

Beaumont    clay 

j£ 

are   represented 

Gravels  and  coarse  sands,  with 

along  the  stream 

0> 

some  small  lenses  and  pockets 

valleys    by    the 

I 

of   red    clay    in    places;    limy 

lowest  and   the 

O" 

Lissie  gravel. 

Thin 

clays,  gravels,  and  limy  con- 

middle   of    the 

to  900 

glomerates  or  "adobe"  in 

three  Pleisto- 

Pleistocene. 

others.        The   fossils  include 

cene  terraces. 

Equus    semipi  attts,     Megal- 

onyx,  etc. 

-Unconformity- 

Fluviatile  deposits  consisting  of  granitic  gravels  in 

and  adjacent  to  certain  drainage  areas;  flints, 

limestone    debris,    and    limy 

conglomerates    in 

others  ;  ferruginous  sands  and  silts,  with  fragments 

Highest  Pleisto- 

of iron  ore,  in  still  others.     In 

the  stream  valleys 

cene   terrace 

these  materials  appear  as  terraces  lying  200  to  225 

(farther   in- 

o-:o 

feet  above  the  level  of  the  present  stream  chan- 

land). 

nels,  and  grading  laterally  into  an  inter-stream  or 

upland  phase  veneering  the  uplands  with  a  sheet 

of  g  avel  where  the  Yegua  and  Jackson  formations 

constitute  the  country  rock,  but  thinning  and  dis- 

appearing south  of  the  Yegua-Catahoula  or  the 

Jackson-Catahoula  boundary. 

No  fossils. 

neon  ormi  y- 

Fluviatile  deposits,   consisting  of  flint  gravel  and 

limestone  debris  embedded  in  a  clay  matrix.     In 

the  plateau  region  west  of  the  Coastal  Plain  the 

Uvalde   forma- 

the formation  appears  as  the  uppermost  terrace  of 

b 

'liocene. 

tion     (late 

0-100 

the  major  streams,  lying  about  350  fe  t  above  the 

•5 

Pliocene). 

levels  of  the  present  stream  channels.     Along  the 

& 

Cretaceous-Tertiary  boundary, 

the  terraces  grade 

laterally  into  an  upland  gravel  deposit,  which  caps 

the  interstream  areas,  but  thins  and  disappears  a 

distance  to  east  and  south. 

GULF  COAST  FIELDS  OF  TEX.  AND  LOUISIANA  367 
CENOZOIC  DEPOSITS  OP  THE  TEXAS  COASTAL  PLAIN — Continued 


Sys- 
tem 

Series 

Formation 

Thick- 
ness 

Lithology  and  Characteristic  Fossils 

b 

1 

Miocene. 

-Unconformity- 

Dewitt   forma- 
tion.0 

Feet 

1,250- 
1,500 

lacustrine  and  littoral  deposits,  consisting  of  cross- 
bedded,  coarse,  gray,  semi-indurated,  highly  cal- 
careous sandstones.  Lenses  of  clay  in  places. 
Aceratherium  and  other  fossils.  East  of  the  Bra- 
zos these  beds  are  almost  completely  overlapped 
by  the  Lissie  gravel.  Seaward,  the  time  equiv- 
alent of  the  Dewitt  formation  is  represented  by 
about  800  feet  of  marine  sands  and  clays,  carrying 
Area  carolinensis  and  other  upper  Miocene  marine 
fossils  and  believed  to  involve  some  of  the  lower 
Pliocene.  These  marine  deposits  do  not  outcrop 
and  are  not  a  part  of  the  lacustrine  Dewitt  forma- 
tion, which  also  includes  some  deposits  of  early 
Pliocene  age. 

Fleming  clay. 

-Unconformity- 

Catahoula 
sandstone. 

200-500 

Palustrine  deposits,  consisting  of  gray,  white,  and 
bluish-white,  bedded,  calcareous  clays,  with  nu- 
merous small  concretions  of  lime  and  some  lenses 
of  sand. 

Oligocene. 

500-800 

Littoral  deposits,  consisting  of  hard,  blue,  semi- 
quartzitic,  noncalcareous  sandstones,  with  inter- 
bedded  lenticular  masses  of  green  clays. 

Eocene. 

Jackson   forma- 
tion.c 

0-250 

Marine  deposits,  consisting  of  calcareous  blue  clays, 
with  large  limestone  concretions.  Carry  Levi- 
fusus  branneri  and  other  Eocene  forms. 

|  Ciaiborne  group. 

Yegua  forma- 
tion. 

375-750 

Palustrine  deposits,  consisting  of  green  clays  with 
concretions  of  selenite;  in  places,  lenses  of  sand 
and  lignite. 

Cook  Moun- 
tain forma- 
tion. 

400 

Palustrine  and  marine  deposits,  consisting  of  lentic- 
ular masses  of  yellow  sand  and  clay;  in  places, 
lenses  of  green  calcareous,  glauconitic,  f  ossiliferoua 
marl.  Beds  of  limonite  and  lignite.  Some  of  the 
clays  carry  fossiliferous  calcareous  concretions. 
Formation  as  a  whole  is  decidedly  ferruginous. 
Fossils:  Ostrea  sellaeformis,  Ostrea  divaricata, 
Anomia  ephippioides,  and  others. 

Mount  Sel- 
man  form- 
ation. 

350 

Palustrine  and  marine  deposits,  consisting  of  red, 
ferruginous,  indurated,  and  probably  altered 
greensand,  with  casts  of  shells,  lenses  of  lignite 
and  clay,  beds  and  concretions  of  limonite.  The 
formation  as  a  whole  is  conspicuously  ferruginous. 
Carries  casts  of  Vcnericardia  planicosta. 

368  GEOLOGY  OF  PETROLEUM 

CENOZOIC  DEPOSITS  OF  THE  TEXAS  COASTAL  PLAIN — Concluded 


Sys- 
tem 

Series 

Formation 

Thick- 
ness 

Lithology  and  Characteristic  Fossils 

Eocene. 

Wilcox  forma- 
tion 

Feet 

800- 
1,100 

Palustrine,  marine,  and  littoral  deposits.  The 
littoral  deposits  comprise  the  Queen  City  sand 
member,  at  the  top  of  the  formation,  consisting  of 
50  to  200  feet  of  white,  porous,  loose,  water-bear- 
ing sands,  with  some  inters  tr  a  tified  clays.  The 
palustrine  deposits  consist  of  lenticular  masses  of 
sand,  clay,  and  lignite,  carrying  large,  especially 
characteristic  concretions  (20  to  30  feet  in  diam- 
eter) of  hard  flintlike  sandstone;  the  palustrine 
clays  are  leaf  bearing,  and  in  places  carry  teeth  of 
Crocodylus  grypus.  The  marine  deposits  consist 
of  calcareous,  glauconitio,  fossiliferous  marls, 
alternating  with  beds  of  sand,  clay,  and  lignite; 
they  are  exposed  only  on  Sabine  River.  Char- 
acteristic fossils  of  the  marine  phase  are  Kellia 
prima,  Natica  aperta,  and  Pleurotoma  silicata. 

Midway  forma- 
tion. 

250-500 

Marine  deposits,  consisting  of  black  and  blue  clays 
with  interbedded  strata  of  limestone  "  and  some 
lenses  of  sand,  which  are  somewhat  rare  north  of 
the  Brazos.  Plejona  limopsis,  Enclimatoceras 
ulrichi,  and  other  fossils. 

°What  is  here  called  the  Dewitt  formation  is  probably  represented  along  the  Sabine  by  the 
beds  described  as  the  Fleming  clay. 


mont,1  a  low  mound  covering  about  225  acres  rises  some  15  feet 
above  the  surrounding  flat  country.  Gas  escapes  in  shallow  pools 
of  water,  and  these  with  sulphur  incrustations  in  the  soil  were  noted 
by  A.  F.  Lucas.  Prospecting  for  sulphur  led  to  the  sinking  of  the 
Lucas  well,  which  at  1,139  feet  proved  to  be  one  of  the  greatest 
gushers  drilled  in  the  United  States,  yielding  75,000  barrels  a  day. 
Other  wells,  closely  spaced,  were  then  sunk,  and  the  field  rapidly 
became  very  productive  and  very  rapidly  declined.  The  beds  are 
Tertiary  or  later.  The  drill  holes  encounter  about  1,000  feet  of 
clay,  sand,  and  gravel.  In  the  lower  portion  of  this  series  some 
limestone  is  found.  A  20-foot  bed  of  porous  limestone  below  this 
series  carries  the  oil.  Below  the  porous  limestone  is  a  thick  body 
of  gypsum  and  rock  salt;  pyrite  and  sulphur  abound.  Some  oil 


^ENNEMAN,  N.  M.  I  Oil  Fields  of  the  Texas-Louisiana  Gulf  Coastal  Plain, 
U.  S.  Geol.  Survey  Bull.  282,  pp.  1-146,  1906. 


GULF  COAST  FIELDS  OF  TEX.  AND  LOUISIANA  369 


370  GEOLOGY  OF  PETROLEUM 

has  been  obtained  also  from  sands  above  the  main  limestone 
horizon.  The  structure  of  the  area  is  domatic.  According  to 
Fenneman,  there  is  an  arching  of  about  200  feet  in  4,000. 

At  Sour  Lake,  20  miles  northwest  of  Beaumont,  gas,  oil,  asphalt, 
and  sour  water  at  the  surface  led  to  drilling.  The  production, 
8,000,000  barrels  in  1903,  rapidly  declined.  The  wells  encountered 
1,600  feet  of  clays  and  sands,  probably  Eocene  and  Miocene,  with 
some  limestone  and  oil;  salt  and  gypsum  appeared  below  the  clay. 
Deep  drilling  brought  in  heavy  production  again  in  1915. 

At  Saratoga,  12  miles  northwest  of  Sour  Lake,  gas,  oil,  and  acid 
waters  were  noted  at  the  surface.  The  general  features  are  said 
to  be  similar  to  those  at  Sour  Lake. 

At  Batson,  7  miles  southwest  of  Saratoga,  drilling  was  done  on 
account  of  gas  bubbles  that  were  observed  to  rise  from  pools  on  a 
flat  country. 

At  Dayton,  about  25  miles  southwest  of  Batson,  gas  escapes  in 
springs.  Below  clays  and  sands  about  600  feet  deep  limestone 
was  encountered,  and  below  the  limestone  salt  and  gypsum. 

Humble,  about  25  miles  west  of  Dayton  and  18  miles  northeast 
of  Houston,  is  a  highly  productive  field.  An  escape  of  gas  led  to 
drilling  a  hill  on  a  low  ridge,  and  a  strong  flow  of  oil  was  encoun- 
tered at  about  1,200  feet.  Recently  deep  drilling  has  brought  in  a 
large  production  on  flanks  of  the  dome. 

At  the  West  Columbia1  dome,  Brazoria  County,  Texas,  wells 
yielding  as  high  as  30,000  barrels  were  brought  in  July,  1920. 
The  surface  rises  18  feet  above  the  surrounding  country.  Barren 
wells,  sunk  near  the  top  of  the  dome,  penetrated  clay,  the  lime- 
stone cap  rock,  then  salt.  The  cap  rock  is  not  productive.  The 
first  well  was  found  on  the  southeast  side  of  the  dome,  about 
2,700  feet  deep,  in  sands  that  rested  against  the  steep  slope  of  the 
salt  dome. 

At  Goose  Creek  in  Harris  County,  Texas,  oil  has  been  found 
in  sands  from  1,000  to  3,400  feet  deep.  No  salt  nor  cap  rock  has 
been  penetrated.  It  is  not  known  whether  the  structure  is  domatic 
or  not.  Some  of  the  wells  yield  as  much  as  3,000  barrels  a  day. 

Damon  Mound  is  one  of  the  most  conspicuous  of  the  surficial 
mounds  in  the  Gulf  coast  region,  and  the  sulphur  outcrops  and  gas 
showings  attracted  attention  immediately  after  the  discovery  of 
Spindletop  in  1901.  Several  wells  were  drilled  at  different  points 

RECALL,  JULIUS:  Oral  Communication. 


GULF  COAST  FIELDS  OF  TEX.  AND  LOUISIANA  371 

on  the  hill  in  1901-1903.  These  encountered  oil  and  salt  and  other 
typical  dome  materials1  but  were  unprofitable.  In  1917  a  gas  well 
came  in  with  an  estimated  open  flow  of  10,000,000  cubic  feet. 
The  sand  was  apparently  encountered  at  a  depth  of  1,447  feet. 
This  well  after  being  brought  under  control  yielded  gas  for  two 
months  and  then  oil,  about  5,000  barrels  daily. 

The  Evangeline  oil  field,2  which  has  been  very  productive,  is 
about  6  miles  northeast  of  Jennings,  Louisiana.  In  this  field  there 
is  a  broad  erosional  depression  about  10  feet  above  sea  level,  which 
occupies  the  side  of  a  low  mound  some  32  feet  above  the  sea.  The 
productive  area  is  about  1  square  mile.  Here,  as  at  Spindletop, 
Texas,  gas  escaped  from  a  spring  in  the  mound.  Because  of  the 
surface  features,  which  are  similar  to  those  of  Spindletop,  a  well 
was  sunk  and  struck  oil  at  a  depth  of  1,822  feet.  The  beds  are 
Miocene  and  Quaternary.  Little  limestone  is  present.  The 
domatic  structure  is  not  so  clearly  shown  as  at  Spindletop.  Ac- 
cording to  Harris  the  oil  has  come  up  along  a  strong  fault  fissure. 

At  Anse  la  Butte,  Louisiana,  gas  bubbling  on  a  small  depression 
ied  to  the  development  of  a  gusher.  Structurally  the  area  is  prob- 
ably a  steep  dome. 

At  Welsh  gas  bubbling  in  a  well  led  to  sinking  a  hole  that  devel- 
oped a  small  oil  area. 

The  New  Iberia  district3  is  in  Iberia  Parish,  Louisiana,  on  Tete 
Bayou,  about  6  miles  east  of  New  Iberia.  Pronounced  escapes  of 
petroleum  gas  and  so-called  "paraffin  beds"  were  discovered  in  this 
vicinity  in  the  summer  of  1916,  and  these  showings  led  to  drilling 
and  discovery.  The  production  to  1918  was  small. 

The  origin  of  the  structure  of  the  Gulf  coast  fields  is  one  of  the 
most  perplexing  problems  in  geology.  Perhaps  the  most  widely 
credited  theory  is  that  of  Harris,4  who  attributes  the  doming  up 
to  the  force  of  crystallization.  He  maintains  that  salt  water  rose 
along  faults  and  fissures  and  solidified,  pushing  up  and  doming  the 
weak  clays.  This  force  has  been  recognized  by  Becker  and  has 

^AYES,  C.  W.,  and  KENNEDY,  WILLIAM:  Op.  cit. 

DEUSSEN,  ALEXANDER:  A  Review  of  Developments  in  the  Gulf  Coast 
Country.  Am.  Assoc.  Pet.  Geol.  Bull,  vol.  2,  pp.  16-37,  1918. 

HARRIS,  G.  D. :  Op.  tit.,  p.  50.    FENNEMAN,  N.  M. :  Op.  tit.,  p.  100. 

'DEUSSEN,  ALEXANDER:  Review  of  Developments  in  the  Gulf  Coast  Coun- 
try. Am.  Assoc.  Pet.  Geol.  Bull.,  vol.  2,  pp.  16-37, 1918. . 

*HARRIS,  G.  D. :  Oil  and  Gas  in  Louisiana.  U.  S.  Geol.  Survey  Bull.  429, 
pp.  1-192,  1910. 


372 


GEOLOGY  OF  PETROLEUM 


LOG  OF  BOLIVAR  No.  1  WELL  OF  NEW  IBERIA  OIL  Co.,  NEW  IBERIA,  LOUISIANA 

(After  Deussen) 


Thickness 

Depth 

Blue  surface  clay  
Gray  sandj  gas                                               

Feet 
70 
110 

Feet 

70 
180 

Water  gravel  

225 

405 

Crust  of  sand  rock                              

1 

406 

Soft  gumbo  and.  boulders 

29 

435 

Hard  gumbo                                

44 

479 

Hard  gumbo 

58 

537 

Packed  sand  

153 

690 

Crystallized  sand;  pyrite  

36 

726 

Soft  gumbo;  streaks  of  crystallized  sand  and  pyrite 
Hard  gumbo 

44 
29 

770 
799 

Hard  gumbo              .              

22 

821 

Hard  gumbo  

29 

850 

Crystallized  sand      

20 

870 

Hard  gumbo 

66 

936 

Dry  sand'  gas          J.  .  .  . 

4 

940 

Very  hard  gumbo  

8 

948 

Oil  sand                    .            

12 

960 

Hard  blue  gumbo  

3 

963 

Hard  gumbo                                        

45 

1  008 

Sandstone  *  pyrite  oil  and  gas 

17 

1  025 

Hard  black  gumbo.    .  .              .                    

18 

1  043 

Sandstone  °  pyrite  oil  and  g-is 

27 

1  070 

Hard  sandrock 

2 

1  072 

Cap  rock        

G 

1  ,078 

been  recently  discussed  by  Taber l  in  connection  with  metalliferous 
deposits.  Not  all  investigators  have  accepted  this  theory.  Nor- 
ton2 has  come  to  the  conclusion  that  the  domes  represent  loci  of  hot 
solutions  containing  lime  carbonate,  sodium  chloride,  lime  sul- 
phate, etc.,  ascending  through  channels  opened  by  faulting  and 
depositing  at  the  surface  great  masses  of  travertine  and  calcareous 
sinter  at  the  time  the  sedimentary  rocks  were  being  deposited. 

ITABER,  STEPHEN:  Pressure  Phenomena  Accompanying  the  Growth  of 
Crystals.  Nat.  Acad.  Sci.  Proc.,  vol.  3,  pp.  297-302,  1917. 

2NoRTON,  E.  G. :  Origin  of  Louisiana  and  East  !Texas  Salines.  Am.  Inst. 
Min.  Eng.  Trans.,  vol.  51,  pp.  502-513,  1915. 


GULF  COAST  FIELDS  OF  TEX.  AND  LOUISIANA  373 

Later  they  were  covered  up,  and  as  compacting  and  subsidence 
took  place  the  strata  sagged  away  from  the  hard  cores,  while  at  the 
same  time  oil  was  concentrated  along  bedding  planes,  rising  in  the 
sandy  or  limy  beds  to  the  tops  of  the  domes,  which  were  obviously 
above  the  old  salt  deposits. 

As  many  of  the  domes,  at  least,  show  quaquaversal  structure, 
it  is  assumed  that  in  this  field  the  occurrences  of  salt  and  oil  are 
generally  in  quaquaversals.  However,  there  are  many  Gulf  dis- 
tricts in  which  the  dome  structure  has  not  been  proved,  and  some 
where  the  principal  structural  features  appear  to  be  faults.  There 
is  a  fairly  uniform  occurrence  of  limestone  or  dolomite  above  the 
salt  and  gypsum;  indeed,  in  many  districts  it  is  this  fractured 
dolomite  that  carries  the  oil.  Its  stratigraphic  position  suggests 
that  the  limestone  is  a  sedimentary  rock.  One  would  not  expect 
materials  deposited  from  hot  water  at  the  surface  of  the  earth  to  be 
as  regularly  layered  as  these.  Nor  does  it  seem  probable  that  fis- 
sures in  the  soft  clay  capping  of  these  zones  would  have  let  out  salt 
water  in  sufficient  quantities  to  deposit  such  enormous  amounts  of 
salt.  Moreover,  if  they  had,  and  if  the  water  could  have  escaped, 
it  would  seem  probable  that  the  oil  would  have  escaped  also.  It  is 
improbable  that  crystals  would  thrust  up  hundreds  or  thousands  of 
feet  of  sedimentary  rock  and  not  fill  the  great  cavities  which  were 
left  in  the  limestone  that  carries  the  oil.  Solutions  move  to  points 
of  less  pressure  and  by  deposition  fill  any  available  openings 
already  formed.  These  cavities  had  not  been  filled  with  salt, 
otherwise  they  could  not  have  served  as  containers  for  the  oil. 

The  domes  of  the  Gulf  Coast  country  have  recently  been  dis- 
cussed by  Deussen,1  who  recognizes  three  classes — shallow  domes, 
domes  of  medium  depth,  and  deep-seated  domes.  In  the  shallow 
domes  the  cap  rock  lies  within  500  or  600  feet  of  the  surface,  and 
salt  within  700  or  800  feet.  Most  of  them  are  accompanied  by 
superficial  mounds,  except  where  the  mounds  have  been  eroded. 
There  is  usually  a  little  oil  in  the  cap  rock,  but  these  domes  as  a 
rule  are  not  very  profitable  commercially.  They  include  Damon 
Mound,  Pierce  Junction,  Blue  Ridge,  Hoskins  Mound,  Ba  ber 
Hill  and  South  Dayton. 

The  domes  of  medium  depth  have  a  cap  rock  about  1,000  to  1,200 
feet  below  the  surface,  and  salt  at  1,200  to  1,600  feet.  The  mounds 
are  not  pronounced.  The  cap  rock  contains  much  oil;  usually 

DEUSSEN,  ALEXANDER:  Am.  Assoc.  Pet.  Geol.  Bull,  vol.  2,  pp.  16-37, 1918. 


374  GEOLOGY  OF  PETROLEUM 

gushers  are  developed  in  these  domes.  They  include  Spindletop, 
Humble,  Sour  Lake,  and  Saratoga. 

The  deep-seated  domes  have  been  drilled  as  deep  as  3,000  feet, 
but  no  cap  rock  and  salt  have  been  encountered.  Overlying 
mounds  are  absent.  The  oil]  produced  in  these  domes  comes  from 
sands  above  the  level  of  the  cap  rock,  possibly  leaking  out  of  it. 
The  deep-seated  domes  include  Goose  Creek,  Edgerly,  Terry,  and 
Welch.  These  may  be  simply  anticlines,  or  there  may  be  under- 
lying salt  domes  that  supply  oil  to  the  sands. 

A  grouping  of  the  wells  of  these  three  classes  shows  that  the 
shallow  ones  and  those  of  medium  depth  occur  near  together,  and 
that  the  deeper  ones  lie  southeast  of  the  shallow  ones,  indicating 
a  dip  of  the  rock  south  and  toward  the  Mississippi  River.  The 
persistence  of  limestone  above  the  salt  suggests  that  many  of  the 
deposits  are  at  the  same  stratigraphic  horizon.  It  is  not  unlikely 
that  these  salt  beds  are  simply  in  anticlines  and  faulted  flexures 
formed  when  the  rocks  of  the  region  were  less  consolidated  than 
they  are  now.  The  salt  was  probably  folded  and  became  thicker 
at  the  crests  of  anticlines,  just  as  has  been  observed  on  the  Englen 
anticline,  at  Stassfurt,  and  in  other  deposits  of  Germany.1  The 
limestone,  being  stronger  than  the  mud  or  clay,  probably  broke 
up  into  blocks,  and  the  shattered  limestone  supplied  reservoirs 
for  the  oil. 

WAN  DER  GRACHT,  W.  A.  I.  M.  V.  W. :  The  Saline  Domes  of  Northwestern 
Europe.  Southwestern  Assoc.  Pet.  Geol.  Bull,  vol.  1,  pp.  85-92,  1917. 

ROGERS,  G.  S. :  Intrusive  Origin  of  Gulf  Coast  Salt  Domes.  Econ.  Geology, 
vol.  13,  pp.  447-485,  1918. 


CHAPTER  XX 

ROCKY  MOUNTAIN  FIELDS 
WYOMING 

General  Features. — Wyoming  is  made  up  of  lofty  mountain 
ranges  and  intermontane  basins.  In  the  northern  part  of  the 
State  there  are  three  great  anticlinal  ranges,  between  which  lie 
two  great  synclinal  basins.  The  Black  Hills,  in  the  northeast 
corner,  extend  into  Wyoming  from  South  Dakota;  west  of  them  is 
the  Big  Horn  Range;  and  west  of  it  the  Shoshone  range  of  Yellow- 
stone Park.  Southwest  of  the  Big  Horn  Mountains  and  nearly 
parallel  to  them  is  the  Wind  River  Range.  The  Front  Range, 
known  in  Wyoming  as  the  Laramie  Range,  occupies  a  large  area 
in  the  southeast  quarter  of  the  State.  In  the  southwest  corner  is 
the  Teton  Range,  about  parallel  to  the  Wasatch  Range  of  northern 
Utah.  The  Owl  Creek  Mountains  lie  southeast  of  the  Shoshone 
Mountains.  In  the  central  and  southern  part  of  the  State  are  the 
Rattlesnake  and  Sweetwater  mountains. 

The  mountains  are,  in  the  main,  anticlinal  folds,  the  tops  of 
which  are  eroded,  so  that  in  some  of  them  the  strata  from  the  pre- 
Cambrian  to  the  Tertiary  are  exposed  (Fig.  161).  On  the  flanks 
of  the  mountain  folds  and  in  the  interiors  of  the  basins  there  are 
many  subordinate  folds,  and  on  these  are  the  principal  oil  fields. 
There  are  altogether  more  than  100  anticlines  and  domes  (Fig.  162). 
Many  of  these  have  been  drilled  without  yielding  oil  or  gas.  About 
a  score  have  proved  productive,  and  more  than  half  of  these  have 
produced  oil  and  gas  in  considerable  quantities.  Noteworthy 
among  them  are  the  Salt  Creek,  Grass  Creek,  Big  Muddy,  Grey- 
bull,  Basin,  Elk  Basin,  Pilot  Butte,  Byron,  Rock  River,  Lost 
Soldier,  Lance  Creek,  and  Buck  Creek  fields. 

A  considerable  part  of  Wyoming  is  underlain  by  Cretaceous 
beds,  and  these  have  supplied  nearly  all  the  oil  produced.  The 
principal  productive  strata  of  the  Cretaceous  are  in  the  Colorado 
group,  which  includes  the  chief  oil-producing  sands  in  central 
Wyoming  and  in  the  Big  Horn  Basin.  In  the  region  north  of 
Lusk,  oil  has  been  produced  recently  from  the  Muddy  sand,  a 

375 


376 


GEOLOGY  OF  PETROLEUM 


PETROLEUM  MARKETED  IN  THE  ROCKY  MOUNTAIN  FIELD  IN  1916  AND  1917, 

IN  BARRELS 


1 

316 

Colorado 

Wyoming 

Montana 

Total 

1916  

197  ,235 

6  ,234  ,137 

44  ,917 

6  ,476  ,289 

1917 

121  ,231 

8  ,978  ,680 

99  ,399 

9  ,199  ,310 

Tertiary  and 
Quaternary 


Comanche  and 
Cretaceous 


Tnassic  and 
Jurassic 


Carboniferous 


Cambrian  and 
OrdovicSan 


Pre -Cambrian 
and  Igneous 


Spale 


FIG.  161. — Sketch  map  of  Wyoming. 


short  distance  below  the  Mowry.  Heavy  black  oil  is  found  in  the 
Embar  of  the  Permian  and  Pennsylvanian.  All  the  reservoir 
rocks  are  sandstones,  except  the  Embar,  which  is  a  porous  lime- 
stone. The  saturation  of  the  rocks  is  lower  than  in  Oklahoma,  and 
the  folds  are  steeper. 

With  a  few  exceptions  only  closed  folds  yield  noteworthy 
amounts  of  oil.  The  closed  folds  are  mainly  domes.  In  one  or  two 
localities  oil  occurs  in  fault  traps.  In  the  Upton-Thornton  field 
the  oil  is  on  a  terrace.  A  considerable  number  of  plunging  anti- 


ROCKY  MOUNTAIN  FIELDS 


377 


clines,  terraces,  and  monoclines  of  low  dip  have  been  drilled,  how- 
ever, without  finding  oil. 

The  oil  of  the  Douglas  field,  which  is  not  very  productive,  has 
probably  accumulated  at  or  near  an  unconformity  between  steeply 
tilted  Cretaceous  rocks  and  flat-lying  Tertiary  beds.  The  Labarge 
and  Spring  Valley  fields,  in  the  southwestern  part  of  the  State,  are 
along  faults.  None  of  these  fields  have  produced  much  oil.  Oil 
seeps  are  common,  one  or  more  being  present  in  at  least  twelve  of 
the  fields. 


FIG.  162. — Map  of  Wyoming  showing  position  of  certain  oil  and  gas  pools 
(black  dots)  and  prospects  (circles.) 

The  water  on  which  the  oil  floats  is  not  all  saline,  although  high 
salinity  is  noteworthy  in  parts  of  the  Salt  Creek  field.  The  low 
salinity  in  the  Grass  Creek  field  is  unusual  for  a  productive  field. 
Fresh  water  below  the  oil  in  the  same  strata  generally  suggests 
communication  with  superficial  sources,  a  condition  which  may 
permit  leakage  of  oil  and  gas.  A  little  water,  not  highly  saline, 
is  found  at  a  depth  of  2,700  feet  in  a  faulted  area  on  the  west  edge 
of  the  Salt  Creek  dome.  The  strata  dip  steeply  toward  the  Salt 
Creek  field.  Water  circulating  down  the  dip  and  rising  in  a  frac- 
tured area  would  sweep  the  oil  sand  free  of  brine  above  that  area. 


378 


GEOLOGY  OF  PETROLEUM 


PETROLEUM  MARKETED,  VALUE.  AND  AVERAGE  PRICE  PER  BARREL  IN 
WYOMING,  1914-1917,  BY  DISTRICTS 


Big  Horn 

Fremont 

Natrona 

Year 

Quantity 

Average 

Quantity 

Average 

Quantity 

Average 

(Barrels) 

Value 

Price  per 

(Barrels) 

Value 

Price  per 

(Barrels) 

Value 

Price  per 

Barrel 

Barrel 

Barrel 

1914  

96,178 

$96,  178 

$1.00 

27,395 

$21,362 

$0,780 

3,421,325 

$1,541,494 

$0.451 

1915  

140,978 

133,457 

.946 

27,660 

15,051 

.544 

3,971,128 

1,985,564 

.500 

1916  

139,854 

150,884 

1.079 

62,564 

87,275 

1.395 

3,933,403 

3,363,364 

.855 

1917  

62,040 

101,549 

1.637 

49,797 

31,113 

.625 

3,910,511 

3,723,291 

.952 

Hot  Springs 

Park 

Converse 

Year 

Quantity 

Average 

Quantity 

Average 

Quantity 

Average 

(Barrels) 

Value 

Price  per 

(Barrels) 

Value 

Price  per 

(Barrels) 

Value 

Price  per 

Barrel 

Barrel 

Barrel 

1914 

(a) 

(a) 

1915  

98,723 

$74,126 

$0.751 

(a) 

(a) 

1916  

1,369,807 

1,336,840 

.976 

720,988 

$695,571 

$0.965 

(a) 

(a) 

1917  

2,756,402 

4,190,774 

1.523 

1,530,264 

2,266,794 

1.481 

665,432 

$726,738 

$1.092 

Year 

Other  Counties 

Total 

Quantity 

(Barrels) 

Value 

Average 
Price  per 
Barrel 

Quantity 
(Barrels) 

Value 

Average 
Price  per 
Barrel 

1914.....  

615,477 
C7,038 
d7,521 
e4,234 

6$20,  158 
C8,820 
d!0,146 
e7,617 

$1.302 
1.254 
1.349 
1.780 

3,560,375 
4,245,525 
6,234,137 
8,978,680 

$1,679,192 
2,217,018 
5,644,080 
11,047,876 

$0.472 
.522 
.905 
1.230 

1915  

1916  

1917  

"Included  in  "Other  Counties." 
bConverse,  Crook,  and  Uinta  Counties. 
cConverse,  Park,  and  Uinta  Counties. 
^Converse  and  Uinta  Counties. 
fUinta  County. 


ROCKY  MOUNTAIN  FIELDS 


379 


SECTIONS  SHOWING  OCCURRENCES  OP  OIL  AND  GAS  IN  SOME  OP  THE  ROCKY 

MOUNTAIN  FIELDS 

(After  Hares.     Correlations  Approximate  and  Incomplete) 
o,  oil;  g,  gas;  +  ,  seeps  or  small  production  of  oil  or  gas 


System  or 
Series 

Spring  Valley 
and  Labarge" 

Grass  Creek6 
and 
Oregon  Basin 

Shoshone 
River.  b 

Greybull* 

Tertiary. 

Wasatch.  -fo. 

Wasatch. 

Wasatch. 

Evanston. 

Fort  Union. 

Fort  Union. 

Fort  Union. 

Tertiary  (?). 

Lance. 

Ilo  (Lance). 

Ilo. 

Cretaceous 

Adaville. 

Meeteetse. 

Meeteetse. 

Montana,  undiffer- 

Pohr> 

Eagle. 

Hilliard 

Cody 

Pierre. 

Cretaceous 

Colorado. 

Basin. 

Frontier,  o. 

Frontier,  o. 

•f 
+ 

Benton. 
Torchlight. 
Peay. 

Aspen,  o. 

Mowry. 

0. 

o.  g. 

Thermopolis.  g. 

0. 

Cretaceous. 

Bear  River,  o. 

Cloverly. 

"Cloverly."  g. 

Cloverly.  o.  g. 

Cretaceous  (?). 

Morrison. 

Morrison,  g. 

Morrison. 

Jurassic. 

Twin  Creek. 

Sundance. 

Triassic. 
Permian. 
Pennsylvania!!. 

"VEATCH,  A.  C.:  Geography  and  Geology  of  a  Portion  of  Southwestern  Wyoming,  with 
Special  Reference  to  Coal  and  Oil.  U.  S.  Geol.  Survey  Prof.  Paper  56,  pp.  157-158,  1907. 
SCHULTZ,  A.  R.:  The  Labarge  Oil  Field,  Central  Uinta  County,  Wyoming.  U.  S.  Geol.  Sur- 
very  Bull.  340,  p.  364,  1908. 

6HEWETT,  D.  F.:  The  Shoshone  River  Section,  Wyoming.  U.  S.  Geol.  Survey  Bull.  541, 
pp.  89-113,  1914,  and  unpublished  data. 

CHINTZE,  F.  F.:  Basin  and  Greybull  Oil  and  Gas  Fields.  Wyoming  State  Geologist's  Office 
Bull.  10,  p.  40,  1914  (1915). 

Fig.  162  is  an  outline  map  showing  the  position  of  the  principal 
mountain  ranges,  the  oil  and  gas  fields,  and  certain  domes  or  other 


380 


GEOLOGY  OF  PETROLEUM 


SECTIONS  SHOWING  OCCURRENCE  OP  OIL  AND  GAS  IN  SOME  OF  THE  ROCKY 

MOUNTAIN  FIELDS — Continued 

(After  Hares.     Correlations  Approximate  and  Sections  Incomplete) 
°>  °il;  g>  gasJ  +j  seeps  or  small  production  of  oil  or  gas 


System  or 
Series 

Basin<* 

Lander* 

Wyoming/ 

Central 
Wyoming;? 

Tertiary. 

UV 

Jndifferentiated 
Fort  Union  and 
Lance. 

Wasatch.  + 

White  River.  + 

Wind  River. 

Absent  or  con- 
cealed. 

Wind  River.  +? 

Laramie. 

?ort  Union. 

^ance. 

Cretaceous 
(Montana). 

L 

Fox  Hills. 

-ewis. 

Mesaverde. 

Meiaverde. 

Vlesaverde. 
Teapot,  -f 
Parkman. 

Cody. 

Mancos. 

+0. 

Fort  Pierre. 

Steele. 
Shannon. 

Cretaceous 
(Colorado). 

Niobrara. 

-f 

Niobrara. 

Carlile. 

Frontier. 
Torchlight.  + 

Peay.  +g. 

Frontier. 
Wall  Creek.  + 

Peay.  + 

Mowry.  +o. 

Fort  Benton. 

Mowry. 

Thermopolis.  + 
Cleverly. 

Thermopolis. 

Cretaceous. 

Dakota. 

Dakota.  + 

+ 

Dakota    + 

Lower  Cretaceous 
(?). 

Lower  Cretaceous. 
Shale. 
Conglomerate.  -J- 

Cretaceous  (?). 

Morrison. 

Morrison. 

Como. 

Morrison.  + 

Jurassic. 

Sundance. 

Shirley. 

Sundance.  + 

Triassic. 

Chugwater.  +o. 

Triassic. 

Chugwater.  + 

Permian. 

Embar.  o. 

Permian. 
Carboniferous. 

Embar.    ^*C^  f 

Pennsylvanian. 

;<AW 

/l/U^/U 

Tensleep.  + 
Amsden. 

i         -       '                     1    '  /'                                                                                                                                'r-U^VOV  . 

rfLupTON,  C.  T.:  Oil  and  Ga3  Near  Basin,  Big  Horn  County,  Wyoming.    "U.  S.  Geol.  Survey 

Bull.  621,  pp.  157-190,  1916. 

eWooDRUFF,  E.  G.:  The  Lander  Oil  Field,  Fremont  County,  Wyoming.  U.  S.  Geol.  Survey 
Bull.  452,  1911. 

'KNIGHT,  W.  C.:  A  Preliminary  Report  on  the  Artesian  Basins  of  Wyoming.  Wyoming 
Univ.  Exper.  Sta.  Bull.  45,  1900.  KNIGHT,  W.  C.,  and  SLOSSON,  E.  E.:  The  Dutton,  Rattle- 
snake, Arago,  Oil  Mountain,  and  Powder  River  Oil  Fields.  Wyoming  Univ.  School  of  Mines, 
Petroleum  ser.,  Bull.  4,  1901. 

"HARES,  C.  J.:  Anticlines  in  Central  Wyoming.  U.  S.  Geol.  Survey  Bull.  646,  pp.  233-279, 
1917. 

AIn  a  later  paper  (U.  S.  Geol.  Survey  Bull.  656,  1917)  HEWErrand  LUPTON  place  the  Mee- 
teetse  above  the  Mesaverde. 


ROCKY  MOUNTAIN  FIELDS 


381 


SECTIONS  SHOWING  OCCURRENCE  OF  OIL  AND  GAS  IN  SOME  OP  THE  ROCKY 

MOUNTAIN  FIELDS — Concluded 

(After  Hares.     Correlations  Approximate  and  Sections  Incomplete) 
o,  oil;  g,  gas;  +,  seeps  or  small  production  of  oil  or  gas 


System  or 
Series 

Salt  Creek 
and 
Powder  River' 

Douglas/ 

Moorcroft 
and 
Newcastle* 

Boulder, 
Colorado' 

Florence, 
Colorado"1 

Tertiary. 

White  River,  o.  g. 

Laramie  (?). 

Fort  Union. 

Fort  Union. 

Tertiary  (?). 

Lance. 

Lance. 

Cretaceous 
(Montana)  . 

Fox  Hills. 

Fox  Hills. 

Fox  Hills. 

Fox  Hills. 

Trinidad.  (?). 

Pierre. 
Parkman. 
Shannon,  o. 

Pierre. 
Parkman  (?). 
Shannon  (?).  + 

Pierre. 

Pierre. 
Hygiene,  o.  g. 
o. 

Pierre, 
o. 

Cietaceous 
(Colorado) 

Niobrara.  o. 

Niobrara. 

Niobrara. 

Niobrara.  o. 

Niobrara. 

Benton. 
Wall  Creek,  o. 

Mowry.  -f- 

Benton.  +o.  g. 
Wall  Creek  (?). 

Mowry. 
(o?) 

Carlile. 

Benton.  o.? 

Carlile. 

Greenhorn. 

Greenhorn. 

Graneros. 
Mowry.  o. 

Graneros. 

Cretaceous. 

Dakota  (?).  + 

"Cloverly."  o.  + 

Dakota,  -f 

Dakota. 

"Dakota."  + 

Fuson.  4- 

Lakota. 

Cretaceous  (?). 

Morrison.  + 

Morrison. 

Morrison. 

Morrison. 

Morrison.  -(- 

Jurassic. 

Sundance.  + 

Sundance. 

Sundance. 

Triassic. 

Chugwater. 

Lykins. 

C  a  r  b  o  n  i  f  er- 
ous. 

Forelle  (?). 
Satanka  (?).   + 
Casper. 

Lyons. 
Fountain. 

''WEGEMANN,  C.  H.:  The  Salt  Creek  Oil  Field,  Natrons  County,  Wyoming.  U.  S.  Geol. 
Survey  Bull.  452,  pp.  37-83,  19 1 1 ;  The  Powder  River  Oil  Field,  Wyoming.  U.  S.  Geol.  Survey 
Bull.  471,  pp.  56-75,  1912.  Compare  with  later  and  more  detailed  correlations,  page  —  and  — . 

'BARNETT,  V.  H.:  The  Douglas  Oil  and  Gas  Field,  Converse  County,  Wyoming.  U.  S.  Geol. 
Survey  Bull.  541,  pp.  49-88,  1914. 

*BARNETT,  V.  H.:  The  Moorcroft  Oil  Field  and  Big  Muddy  Dome,  Wyoming.  U.  S.  Geol. 
Survey  Bull.  581,  pp.  83-117,  1914.  DARTON,  N.  H.:  Preliminary  Report  on  the  Geology  and 
Underground  Water  Resources  of  the  Central  Great  Plains.  U.  S.  Geol.  Survey  Prof.  Paper  32, 
np.  334,  364,  379-388,  1905. 

*FENNEMAN,  N.  M.:  Geology  of  the  Boulder  District,  Colorado.  U.  S.  Geol.  Survey  Bull. 
265,  pp.  76-98,  1905. 

mWA8HBURNE,  C.  W. :  The  Florence  Oil  Field,  Colorado.  U.  S.  Geol.  Survey  Bull  381, 
pp.  517-544,  1910. 

structural  features  that  are  barren  or  have  not  yet  been  fully 
tested.  A  number  of  fields  yield  gas  or  gas  with  relatively  little 
oil.  The  gas  fields  include  Oregon  Basin,  Buffalo  Basin,  Bonanza, 


382  GEOLOGY  OF  PETROLEUM 

Big  Sand  Draw,  Sweetwater,  Sheep  Mountain,  Oil  Mountain,  Pine 
Dome  and  North  Casper. 

Salt  Creek.— The  Salt  Creek  field1  is  about  40  miles  north  of 
Casper  and  includes  a  productive  area  of  7  square  miles.  It  is  the 
most  productive  field  in  Wyoming  and  yields  a  high-grade  paraffin 
oil,  greatly  prized  on  account  of  its  gasoline  content.  Indications 
of  oil  in  the  Salt  Creek  field  include  several  oil  and  gas  seeps  in 
shale,  deposits  of  ozokerite  along  fault  planes  in  shale,  and  oil  seeps 
from  the  Shannon  sandstone.  Several  oil  and  gas  seeps  from  the 
shale  were  known  prior  to  the  drilling  of  the  discovery  well  in  the 
Salt  Creek  anticline. 

Oil  is  found  in  four  sands — the  Shannon,  of  the  Montana;  and 
the  first  Wall  Creek,  second  Wall  Creek,  and  third  Wall  Creek  of 
the  Colorado.  Each  of  these  sandstones  is  capped  by  shale.  The 
dominant  feature  of  the  structure  is  a  broad  anticline  18  miles 
long  and  about  6  miles  wide  on  which  there  are  two  broad  domes — 
the  Salt  Creek  dome  and  the  Teapot  dome.  The  east  limb  of  the 
anticline  has  a  gradual  dip,  the  west  limb  is  more  abrupt.  Several 
faults  strike  across  the  domes;  most  of  them  are  normal  faults  and 
have  displacements  ranging  from  5  to  100  feet.  Some  thrust 
faults  are  present. 

The  wells  produce  both  oil  and  gas.  Some  are  gushers.  On  three 
sides  of  the  Salt  Creek  dome  (Fig.  37,  p.  131)  the  variation  in  posi- 
tion of  the  oil  is  not  over  50  feet,  but  on  the  north  end,  as  stated  by 
Wegemann,  the  oil  extends  downward  about  150  feet  lower,  prob- 
ably because  the  gathering  area  was  greater  in  that  direction. 
The  oil  is  under  pressure,  and  much  gas  is  dissolved  in  it  rather 
than  segregated  in  pools  above  the  oil. 

Oil  has  been  found  also  in  the  second  Wall  Creek  sand,  which  is 
about  25  feet  thick  and  lies  250  feet  below  the  first  Wall  Creek 
sand.  Wegemann  states  that  the  productive  area  in  this  sand  is 
probably  larger  than  the  productive  area  in  the  first  Wall  Creek 
sand.  In  nearly  all  wells  drilled  in  the  Salt  Creek  field  some  oil 
is  encountered  in  shale.  (See  p.  157.) 

The  Teapot  dome,  to  the  south,  is  included  in  a  naval  reserve. 

At  the  crest  of  the  dome  the  first  Wall  Creek  sand  is  reached  at 
a  depth  of  about  1,000  feet.  The  first  Wall  Creek  sand  is  about 

WEGEMANN,  C.  H.  i  The  Salt  Creek  Oil  Field,  Wyoming.  U.  S.  Geol. 
Survey  Bull.  670,  1917;  also  Bull  452,  pp.  37-84,  1911. 


ROCKY  MOUNTAIN  FIELDS 


383 


FORMATIONS  IN  SALT  CREEK  OIL  FIELD,  WYOMING 
(After  Wegemann) 


System 

Series 

Group 

Formation 

Character 

Thickness 
(Feet) 

Tertiary. 

Eocene. 

Wasatch  formation. 

Yellow  sandstone, 
gray  shale  and  coal. 

2,400 

Fort  Union  formation. 

Fine-grained  bluish- 
white  sandstone 
and  gray  shale. 

2,000 

Tertiary  (?) 

(?) 

Lance  formation. 

Concretionary  buff 
sandstone  and 
shale. 

3,200 

Cretaceous. 

Upper  Cre- 
taceous. 

Montana  . 

Lewis  shale  with  thick 
sandstone  at  top  and 
another  sandstone  in 
middle. 

Sandstone,  white  to 
brown,  and  gray 
shale. 

1,400 

Mesaverde    formation, 
including    Parkman, 
and     Teapot     sand- 
stone members. 

Shale,  sandstone,  thin 
coal  beds. 

845 

Steele  shale,  including 
Shannon    sandstone 
member.     Carries 
oil. 

Buff  sandstone  anc 
gray  shale. 

2,275 

Colorado  . 

Niobrara  shale. 

Light-colored  shale 
in  parts  somewha 
arenaceous. 

735 

Benton  shale. 

Dark  shale. 

220 

Wall  Creek  sand- 
stone member  and 
lower  sands  with 
interbedded  shale. 
Carry  oil. 

Buff  to  white  sand- 
stone and  gray 
shale. 

685 

Dark  shale. 

250 

Mowry  shale  mem- 
ber. 

Firm     slaty    shale 
usually  forming  es- 
carpment. 
Weathers   light   gray 
and  bears  fish  scales. 

280 

Dark  shale. 

205 

Lower  Cre- 
taceous. 

Cleverly  formation. 

Thin  sandstone  and 
dark  shale. 

150 

Conglomerate. 

Cretaceous  (?) 

(?) 

Morrison  formation. 

Variegated  shale  with 
several  sandstone 
beds. 

250 

Jurassic. 

Upper    Ju- 
rassic. 

Sundance  formation. 

Shale,  limestone,  and 
sandstone. 

150 

125  feet  thick  and  consists  of  medium-grained  dirty-gray  sandstone 
containing  thin  calcareous  beds  and  numerous  lenses  and  layers  of 
sandy  shale  ranging  in  thickness  from  a  fraction  of  an  inch  to  sev- 
eral feet.  The  distribution  of  the  oil  in  the  sand  is  dependent  on 


384  GEOLOGY  OF  PETROLEUM 

differences  in  the  porosity  of  the  layers  composing  it,  due  to  differ- 
ences in  the  sizes  of  the  sand  grains  and  the  amount  of  cementing 
material  between  them.  The  porosity  of  the  sand  in  the  several 
layers  of  the  formation  differs  greatly.  A  specimen  of  massive 
sandstone  from  the  upper  part  of  the  Wall  Creek,  collected  by 
Wegemann  and  tested  by  Van  Orstrand,  has  a  porosity  of  25.8  per 
cent;  another  specimen,  somewhat  shaly,  taken  near  the  base  of 
the  formation,  has  a  porosity  of  20.4  per  cent;  and  a  specimen  from 
one  of  the  thin  layers  of  calcareous  sandstone,  called  by  the  drillers 
"shells,"  has  a  porosity  of  only  7.6  per  cent. 

Owing  to  variations  in  the  character  of  the  sand,  oil  is  encoun- 
tered in  the  wells  in  pay  streaks;  in  some  places  the  "pay"  is  found 
at  the  very  top  of  the  sand ;  in  others  it  is  some  distance  below  the 
top,  only  small  amounts  of  oil  and  gas  being  found  when  the  sand 
is  first  struck.  There  are  no  dry  holes  within  the  known  oil  pool, 
some  part  of  the  sand  being  capable  of  commercial  production 
wherever  it  is  tapped. 

The  distribution  of  the  oil  about  the  Salt  Creek  dome  is  unusu- 
ally regular.  The  line  marking  the  contact  of  the  oil  pool  with  the 
water  that  occupies  the  sand  on  the  flanks  of  the  fold  below  the  oil 
varies  only  about  150  feet  in  elevation  in  the  entire  circuit  of  the 
dome,  lying  between  3,425  and  3,575  feet  above  sea  level.1 

The  first  commercial  wells  in  the  Salt  Creek  field  were  drilled  in 
the  Shannon  pool,  which  is  at  the  north  end  of  the  dome,  about  3 
miles  north  of  the  present  town  of  Salt  Creek.  The  oil  is  obtained 
from  the  Shannon  sand,  which  lies  2,000  feet  above  the  Wall  Creek 
and  forms  the  rim  rock  of  the  Salt  Creek  pool.  The  Shannon  sand 
is  encountered  in  the  Veils  at  Shannon  at  depths  ranging  from  700 
to  1,000  feet.  It  consists  of  two  ledges  separated  by  30  or  40  feet 
of  sandy  shale.  The  upper  ledge  of  sandstone  is  about  40  feet 
thick,  and  the  lower  one  50  feet.  The  oil  is  confined  to  the  lower 
ledge,  the  upper  being  water  bearing.  The  porosity  of  the  sand, 
determined  by  Van  Orstrand,  is  26.7  per  cent. 

The  Shannon  wells  are  small,  the  average  well  producing  daily 
from  5  to  15  barrels  of  heavy  paraffin-base  oil.  The  pool  appears 
to  contain  not  more  than  160  acres.  Some  of  the  wells  flowed 
slightly  when  first  struck,  but  all  of  them  were  pumped.  No  oil 
is  now  being  taken  from  them.  The  pool  is  on  the  pitching  north 

WEGEMANN,  C.  H.:  The  Salt  Cre^  Oil  Field,  Wyoming.  U.  S.  Geol. 
Survey  Bull,  670,  p.  27,  1917. 


ROCKY  MOUNTAIN  FIELDS  385 

end  or  "nose"  of  the  Salt  Creek  anticline,  at  a  place  where  the  fold 
is  narrowed  abruptly.  The  oil  extends  farther  down  the  end  of  this 
fold  than  it  does  on  the  western  flank.  The  limits  on  the  east  are 
not  accurately  determined.1 

Powder  River. — The  Powder  River  or  Tisdale  field2  is  a  dome 
southeast  of  the  Big  Horn  Mountains.  The  strata  in  which  the 
oil  occurs  are  lower  in  the  geologic  column  than  those  which  bear 
oil  at  Salt  Creek.  The  oil  of  the  Powder  River  field  is  a  heavy 
lubricating  oil. 

The  Powder  River  dome  is  roughly  outlined  in  plan  by  the  out- 
crop of  the  Wall  Creek  sandstone.  The  dome  is  a  somewhat  irreg- 
ular oval  16  miles  long  from  north  to  south  and  10  miles  wide  from 
east  to  west,  its  axis  trending  approximately  north.  About  15 
miles  north  and  a  little  west  of  the  highest  point  of  the  dome  is  a 
smaller  but  similar  dome,  which  lies  just  west  of  the  village  of 
Kaycee.  The  two  domes  are  connected  by  a  low  anticlinal  arch 
and  may  be  considered  parts  of  a  single  structural  feature  30 
miles  long. 

Oil  has  been  found  in  five  different  beds  in  the  Powder  River 
field.  Of  these  the  lowest  is  in  the  Sundance,  a  small  quantity  of 
oil,  along  with  brackish  water,  rising  from  the  upper  strata  of  that 
formation  in  the  SW.  ^  sec.  33,  T.  41  N.,  R.  81  W.  A  massive 
sandstone  about  6  or  7  feet  thick  near  the  base  of  the  Morrison 
formation  contains  a  small  quantity  of  oil  in  the  NE.  J^  sec.  33, 
T.  41  N.,  R.  81  W.,  where  a  tunnel  has  been  driven  into  the  sand- 
stone. In  Oil  Canyon  a  small  oil  seep  was  noted  in  a  sandstone 
near  the  middle  of  the  Morrison.  In  the  Mowry  shale  member  oil  is 
reported  in  the  well  in  Oil  Canyon,  where  a  few  quarts  was  obtained 
at  a  depth  of  about  300  feet.  The  principal  reservoir  of  oil  in  the 
field,  however,  is  the  coarse  conglomeratic  sandstone,  56  feet  thick, 
which  is  probably  the  Cloverly.  It  has  been  prospected  with 
results  that  are  not  encouraging. 

The  open  wells  in  Trail  Canyon,  on  the  crest  of  a  secondary  fold, 
which  here  forms  also  the  axis  of  the  anticline,  obtain  oil  from  the 
Cloverly  (?)  sandstone.  It  has  been  suggested  that  the  oil  from 
the  Embar  formation  has  risen  to  the  sandstone  beds  above. 

'WEGEMANN,  C.  H.:  Op.  tit.,  p.  33. 

2WEGEMANN,  C.  H.  i  The  Powder  River  Oil  Field,  Wyoming.  U.  S.  Geol. 
Survey  Bull.  471,  p.  56,  1912. 


386  GEOLOGY  OF  PETROLEUM 

Big  Muddy  Dome. — The  Big  Muddy  dome1  is  in  Converse  and 
Natrona  Counties,  near  the  North  Platte  River,  about  15  miles 
east  of  Casper.  The  following  generalized  section  shows  the 
character  and  thickness  of  the  Mesozoic  and  later  formations  and 
their  relations  to  each  other: 

The  Big  Muddy  dome  is  a  slight  arch  of  the  strata  extending 
over  an  area  of  about  72  square  miles. 

At  the  surface  that  part  of  the  Pierre  formation  which  lies  below 
the  Parkman  sandstone  member  crops  out.  The  outline  of  the 
dome  is  shown  by  the  outcrop  of  the  Teapot  sandstone  member. 
Oil  is  obtained  from  the  Shannon  sand,  from  a  stray  sand,  and  from 
the  Wall  Creek  sand  of  the  Colorado.  The  depth  of  the  Shannon 
ranges  from  950  to  1,150  feet;  the  Wall  Creek  is  about  2,000  feet 
deeper. 

In  the  field  proper  there  are  two  anticlines — a  northerly  one 
trending  east,  on  which  oil  is  obtained,  and  another  in  the  south- 
western part  of  the  field  trending  northeast  and  nearly  east.  These 
are  separated  by  a  shallow  syncline.  A  well  on  the  southwestern 
anticline  obtained  water.  This  fold  may  be  cut  off  by  a  fault  to 
the  southwest. 

Douglas. — The  Douglas  oil  and  gas  field2  (Brenning  Basin)  lies 
west  of  Douglas,  in  Converse  County.  Oil  springs  are  found  at 
many  places  in  this  region. 

The  White  River  formation  in  the  Douglas  field  rests  unconform- 
ably  on  the  upturned  edges  of  the  older  rocks,  which  include  nearly 
all  the  beds  of  the  Colorado  and  Montana  groups,  both  of  which 
are  known  to  yield  oil  in  the  Salt  Creek  field  and  near-by  areas. 
Hewett  believes  that  the  oil  in  migrating  upward  along  bedding 
planes  and  through  porous  sandstone  finds  a  barrier  when  it  reaches 
the  White  River  formation,  so  that  oil  and  gas  accumulate  near 
this  line,  penetrating  the  White  River  only  where  they  encounter 
lenses  of  porous  material  or  fault  planes. 

Two  grades  of  oil  are  produced — a  heavy  lubricating  oil  and  a 
light  oil  of  good  quality.  The  gas  is  rich  in  propane  and  butane. 
The  field,  though  extensively  prospected,  has  not  made  a  large 
production. 

IBARNETT,  V.  H. :  Possibilities  of  Oil  in  the  Big  Muddy  Dome,  Converse  and 
Natrona  Counties,  Wyoming.  U.  S.  Geol.  Survey  Bull.  581,  pp.  105-117, 1915. 

HEWETT,  D.  F. :  The  Douglas  Oil  and  Gas  Field,  Converse  County,  Wyom- 
ing. U.  S.  Geol.  Survey  Bull.  541,  pp.  89-113,  1914. 


ROCKY  MOUNTAIN  FIELDS 


387 


GEOLOGIC  FORMATIONS  IN  OR  NEAR  POWDER  RIVER  OIL  FIELD,  WYOMING 

(After  Wegemann) 


System 

Series 

Group 

Formation 

Description 

Thick- 
ness 
(Feet) 

Cretaceous. 

Upper  Cre- 
taceous. 

Montana 
(4.350  feet)  . 

Fox    Hills    sand- 
stone. 

White  sandstone  and  shale. 
Marine. 

700? 

Pierre  formation  (3,650  feet). 

Shale  with  several  sandstone 
beds,  including  that  which 
forms  Little  Pine  Ridge. 
Marine. 

1,000 

P  a  r  k  m  a  n 
sandstone 
member. 

Massive  buff  sandstone  over- 
lain by  shale  and  thin  coal 
beds.  Marine  and  fresh 
water. 

350 

Shale  with  sandstone  stratum 
250  feet  above  its  base. 
Marine. 

1,100 

Shannon  sand- 
stone lentil. 

Oil-bearing  horizon  near  base. 
Marine. 

175 

Gray  shale.     Marine. 

1,025 

Colorado 
(2,405  feet). 

Niobrara  shale. 

Light-colored  shale,  in  part? 
somewhat  arenaceous.  Ma- 
rine. 

735 

Benton  shale  (1,670  feet). 

Dark  shale,  several  calcareous 
beds.  Marine. 

220 

Wall  Creek 
sandstone 
lentil. 

Buff  sandstone,  ripple  marked 
and  cross-bedded.  Petrified 
wood,  marine  shells,  and 
fish  teeth.  The  principal  oil 
sand  of  Salt  Creek. 

80 

Dark  shale,  several  sandstone 
beds.  Marine. 

800 

Mowry  shale 
member. 

Firm  slaty  shale,  usually  form- 
ing escarpment.  Weathers 
light  gray  and  bears  fish 
scales.  Marine. 

300 

Dark  shale  with  one  thin,  per- 
sistent, strongly  ripple- 
marked  sandstone. 

270  • 

Dakota  (?)  sand- 
stone. 

Conglomeratic  sandstone,  oil 
bearing.  Fresh  water. 

56 

Jurassic  (?). 

Morrison  forma- 
tion. 

Variegated  shale  with  several 
sandstone  beds  which  in 
certain  localities  bear  oil. 
Fresh  water. 

250 

Jurassic. 

Sundance  forma- 
tion. 

Shale  and  limestone  in  upper 
part;  white  sandstone  in 
lower  part. 

275 

This  district  has  not  produced  profitable  quantities  of  oil,  and 
its  imoortance  is  problematic. 


388 


GEOLOGY  OF  PETROLEUM 


GENERALIZED  SECTION  OF  FORMATIONS  INVOLVED  IN  THE  BIG  MUDDY  DOME, 

WYOMING 
(After  Barnett) 


1  c*03 

Quaternary.  2  << 

Series 

Group 

Formation" 
and 
Member 

Character 

Type  of  Topography 
and  Soil 

Thick- 
ness 
(Feet) 

-Unconformity- 
White  River  for- 
mation. 

-Unconformity- 
Lance   forma- 
tion. 

Alluvium,  gravel,  and 
sand. 

Sand  dunes,  gravel- 
topped  hills,  and  val- 
ley flats. 

25  + 

Tertiary. 

Oligocene. 

Clay,  conglomerate, 
and  sandstone. 

Flat-topped  hills  and 
gentle  slopes;  thin 
soil. 

1,000 

Cretaceous.  Tertiary  (?). 

V 

c 

Friable  sandstone  and 
shale,  with  local 
beds  of  coal. 

Rolling  hills  and  broad 
gentle  slopes;  thin, 
sandy  soil  and  alkali 
flats. 

200  + 

Upper 
Cretaceous. 

Montana  . 

Fox  Hills  forma- 
tion, base  un- 
certain. 

Friable  sandstone  and 
shale  with  local  coal 
beds  near  top. 

Ridges  of  sandstone 
and  valleys  in  shale; 
sandy  soil. 

860 

c 

01 

c 

8 

Sandy  shale. 

Valleys;  thin  clay  soil. 

400 

Teapot  sand- 
stone mem- 
ber. 

Gray  and  buff  sand- 
stone and  carbona- 
ceous shale. 

Low  ridges,  barren  rock 
slopes,  and  pine-clad 
hills. 

160 

Sandy  shale. 

Valleys;  thin  clay  soil. 

320 

P  a  r  k  in  a  n 
sandstone 
member. 

Friable  sandstone  and 
beds  of  shale  and 
coal. 

Ridges  of  some  promi- 
nence and  broad, 
grassy  slopes. 

330 

Dark  shale. 

Broad  valleys;  thin 
soil. 

2,000 

Colorado  . 

\*iobrara  shale  . 

Gray  to  buff  calcar- 
eous shale. 

Low  rounded  ridget 
and  brown  slopes. 

100-650 
200 

Benton  snale. 

Dark  shale. 

Marrow  valleys;  thin 
soil. 

Wall  Creek 
sandstone 
member. 

Gray  and  buff  sand- 
stone and  beds  of 
shale. 

Ledges  and  hogback 
ridges  covered  with 
small  pines. 

100-200 

Dark  shale  including 
Mowry  shale  mem- 
ber. 

Broad  valley  with  low, 
rounded  pineclad 
ridge  of  Mowry  shale. 
Thin  soil. 

1,200 

Lower 
Cretaceous. 

Cleverly  forma- 
tion. 

3uff  sandstone  and 
shale  with  conglom- 
erate in  lower  part. 

Ledges,  hogback  ridges, 
and  barren  slopes  of 
rock;  thin  sandy  soil. 

140 

I 

CJ 

3 

Morrison  forma- 
tion. 

Green,  buff  gray,  and 
maroon  shale  and 
thin  beds  of  sand- 
stone. 

Gentle  slopes  below 
ridges  of  Cleverly 
rocks. 

700 

Upper 
Jurassic. 

Sundance   for- 
mation. 

Greenish-gray  lime- 
stone and  sand- 
stone. 

ROCKY  MOUNTAIN  FIELDS  389 

Lander. — The  Wind  River  Range  lies  southwest  of  the  Big  Horn 
Basin  and  its  southwestern  bordering  range,  the  Owl  Creek  Moun- 
tains. The  Wind  River  Range  is  an  anticlinal  uplift  striking 
northwest.  Northeast  of  it  there  is  a  foothill  fold,  the  Shoshone 
anticline,  40  miles  or  more  long,  that  strikes  northwest,  parallel  to 
the  Wind  River  Range.  This  anticline  has  an  undulating  crest, 
developing  four  elongated  domes.  These  from  northwest  to  south- 
east are  the  Sage  Creek  dome;  the  Plunkett  dome  (Big  Popo  Agie), 
near  Lander;  the  Dallas  dome  (Little  Popo  Agie) ;  and  the  Sweet- 
water  dome.  Along  the  crest  of  the  anticline  the  Red  Beds  (Chug- 
water),  of  Triassic  age,  crop  out.  Wells  drilled  on  the  crest 
encounter  the  Embar  (Carboniferous),  which  yields  a  heavy  oil. 
The  Embar1  consists  of  limestone,  some  of  it  shaly  a'nd  cherty,  and 
of  shale.  Two  members  consist  of  very  shaly  sandstone  contain- 
ing a  large  percentage  of  lime  carbonate  and  some  bituminous 
matter  which  comes  to  the  surface  in  oil  seeps.2  Woodruff  con- 
siders the  Embar  the  main  source  of  oil  in  the  region,  although  oil 
is  found  also  in  overlying  formations.  The  Chugwater  (Red 
Beds),  above  the  Embar,  consists  of  red  shales  and  sandstones 
nearly  1,500  feet  thick.  It  contains  lenses  of  gypsum.  Above 
the  Chugwater  are  Mesozoic  shale,  sandstone,  and  limestone. 

The  oil  is  found  along  the  top  of  the  anticline.  On  the  Little 
Popo  Agie  dome  there  is  a  thrust  fault  2J^  miles  long  with  a  throw 
of  about  1,180  feet.  No  springs  occur  along  the  line  of  the  fault, 
and  neither  oil  seeps  nor  asphalt  beds  were  noted  near  it.  The 
fault  is  believed  to  extend  downward  to  the  oil-bearing  strata,  but 
the  abundant  shale  in  the  Chugwater  formation  has  probably 
sealed  the  break  and  prevented  the  escape  of  gas  or  oil.  Several 
oil  seeps  and  tar  springs,  however,  occur  along  the  axis  of  the  anti- 
cline. It  is  these  springs,  together  with  the  anticlinal  structure, 
that  led  to  the  prospecting  for  oil.  Most  of  the  wells  show  gas3. 
The  oil  flows  from  several  wells,  but  some  are  pumped.  The  oil 
is  a  heavy  oil  with  an  asphalt  base,  and  production  is  small. 

Maverick  Springs,  Fremont  Ceunty. — The  Maverick  Springs,3 
district  is  in  the  Wind  River  Basin,  just  south  of  Owl  Creek 

WOODRUFF,  E.  G. :  The  Lander  Oil  Field/  Fremont  County,  Wyoming 
U.  S.  Geol.  Survey  Bull.  452,  pp.  1-36,  1911. 

Z0p.  cit.,  p.  12. 

COLLIER,  A.  J.:  Anticlines  Near  Maverick  Springs,  Fremont  County, 
Wyoming.  U.  S.  Geol.  Survey  Bull  711-H,  pp.  149-166,  1920. 


390  GEOLOGY  OF  PETROLEUM 

Mountains.  Three  domes  are  developed  along  an  axis  that  strikes 
northwest.  These  are,  from  northwest  to  southeast,  the  Circle 
Ridge  Dome,  the  Big  Dome,  and  the  Little  Dome. 

On  the  Circle  Ridge,  the  top  of  the  Embar  formation  is  exposed. 
In  the  Big  Dome  the  Chugwater,  composed  of  sandstones,  shales, 
and  gypsum,  covers  the  Embar,  which  consists  of  limestone,  shale, 
and  phosphate  rock,  with  some  sandy  layers  (Fig.  163).  The  oil 
is  found  in  a  sand  in  the  Embar  group  and  is  developed  on  the  Big 
Dome  which  has  several  hundred  feet  of  closure.  It  is  a  heavy 
asphaltic  oil  like  that  obtained  at  Lander. 

Pilot  Butte.— The  Pilot  Butte  field1  is  near  the  center  of  Fre- 
mont County;  in  the  west-central  part  of  the  State,  about  40  miles 
southwest  of  Thermopolis  and  26  miles  north  of  Lander.  It  is  on 
an  elongated  dome  that  lies  a  little  east  of  north  of  the  north  end 
of  the  Shoshone  anticline  and  is  an  echelon  fold  or  uplift  on  its 
basinward  flank.  The  oil  produced  has  a  paraffin  base  and  is 
obtained  from  Cretaceous  sandstone.  The  oil  is  found  in  an  inter- 
bedded  sandstone  about  1,500  feet  above  the  base  of  the  Pierre. 
A  sandstone  on  Dry  Creek  in  the  Pierre  about  1,450  feet  above  the 
base  is  correlated  with  the  upper  oil  sand  of  Pilot  Butte.  The 
sandstone  here  is  a  friable,  porous  buff  rock  that  has  a  few  streaks 
of  grit  with  grains  as  much  as  a  quarter  of  an  inch  in  diameter. 
It  is  overlain  and  underlain  by  sandy  shales,  and  the  total  thick- 
ness of  the  sandy  zone  is  40  feet;  the  sand  proper  is  about  15  feet 
thick.  This  horizon  is  approximately  the  same  as  that  of  the 
Shannon  sandstone,  which  produced  oil  in  the  Salt  Creek  and  Big 
Muddy  fields.  Other  sands  should  be  encountered  below. 

Central  Wyoming. — The  city  of  Casper  is  the  most  important 
center  of  refining  in  Wyoming  and  the  headquarters  of  many  pro- 
ducing and  prospecting  companies.  The  Salt  Creek  field  is  north- 
east of  Casper,  and  the  Big  Muddy  dome  is  about  15  or  20  miles 
to  the  east.  To  the  west  of  Casper  for  about  100  miles  extending 
nearly  to  Lander,  there  is  a  broad  belt  of  Cretaceous,  Tertiary,  and 
Quaternary  rocks.  The  Cretaceous  is  thrown  into  folds  nearly  all 
of  which  strike  northwest.  These  folds  have  been  mapped  and 
described  by  Hares. 2 

JZiEGLER,  VICTOR:  The  Pilot  Butte  Oil  Field,  Fremont  County,  Wyoming. 
Wyoming  Geol.  Survey  Bull  13,  p.  143,  1916. 

2HARES,  C.  J. :  Anticlines  in  Central  Wyoming.  U.  S.  Geol.  Survey  Bull. 
641,  pp.  233-279,  1917. 


ROCKY  MOUNTAIN  FIELDS 


391 


FIG.  163. — Sections  of  Big  Dome  and  of  Little  Dome,  Maverick  Springs 
region,  Fremont  County,  Wyoming.  (After  Collier.)  Oil  is  discovered  on  the 
Big  Dome  in  the  Embar  formation. 


392  GEOLOGY  OF  PETROLEUM 

The  Carboniferous  and  Cretaceous  formations  which  produce  oil 
in  other  Rocky  Mountain  fields  are  well  developed  in  central 
Wyoming,  and  in  places  the  oil  seeps  from  them,  but  in  only  a  few 
places  are  these  formations  covered  by  impervious  shale  and  within 
reach  of  the  drill  in  folds  favorable  for  the  accumulation  of  oil  and 
gas.  The  noteworthy  folds,  according  to  Hares,  are  the  Pine  dome, 
the  Oil  Mountain  ianticline,  the  anticlines  between  Poison  Spider 
and  South  Casper  creeks,  and  the  Emigrant  Gap,  Iron  Creek, 
North  Casper  Creek,  and  Bates  Hole  anticlines.  The  Cretaceous 
oil  sands  are  below  the  surface  in  the  Big  Sand  Draw  anticline,  in 
the  anticline  southwest  of  Powder  River,  and  in  the  dome  (?)  on 

Wallace  Creek. 

i      * 

Rock  Rivfer. — The  Rock  River  field  is  near  the  eastern  border  of 
Carbon  County.  No  reports  showing  the  structure  of  this  field 
have  been  published,  but  the  stratigraphy  and  structure  of  areas 
between  Rawlins  and  Medicine  Bow,  which  lie  just  west  of  it,  have 
been  described  by  Veatch.1 

Lost  Soldier. — The  Lost  Soldier  field  is  in  northeastern  Sweet- 
water  County.  It  lies  on  an  anticline, 2  on  which  the  Niobrara  is 
exposed.  A  light-gravity  oil  is  obtained  from  the  Wall  Creek 
sandstone  of  the  Frontier  formation. 

Moorcroft. — In  eastern  and  northeastern  Wyoming  the  regional 
dip  is  southward,  away  from  the  Black  Hills  uplift.  The  rocks 
outcropping  are  indicated  in  the  accompanying  table.  At  several 
places  subordinate  folds  have  been  identified  on  the  southward- 
dipping  monocline,  and  some  of  these  have  been  prospected  for  oil. 

The  Moorcroft  oil  field3  lies  12  miles  north  of  the  town  of  Moor- 
croft.  Seeps  are  found  in  the  Fuson  shale,  the  Dakota  sandstone, 
and  the  Graneros  formation.  Prior  to  1888  oil  was  pumped  from 
a  well  and  gathered  from  oil  springs  and  sold  in  mining  towns  of  the 
Black  Hills.  The  district  contains  a  heavy  paraffin  oil  and  also  a 
heavy  asphaltic  oil.  The  sandstone  of  the  Graneros  shale  (Ben- 
ton)  is  the  main  oil-bearing  bed.  Numerous  test  wells  have  failed 
to  reveal  commercial  supplies  (1919). 

VEATCH,  A.  C.:  Coal  Fields  of  East-Central  Carbon  County,  Wyoming. 
U.  S.  Geol.  Survey  Bull.  316,  pp.  244-263,  1907. 

2ZiEGLER,  VICTOR:  Popular  Oil  Geology,  p.  94,  New  York,  1918. 

3BARNEfr,  V.  H.:  The  Moorcroft  Oil  Field,  Crook  County,  Wyoming. 
U.  S.  Geol.  Survey  Bull.  581-C,  pp.  83-105,  1915. 


ROCKY  MOUNTAIN  FIELDS 


393 


GENERALIZED  SECTION  OF  ROCKS  IN  THE  MOOBCROFT  OIL  FIELD,  WYOMING 

(After  Barnett) 


Sys- 
tem 

Series 

Group 

Formation 

Character 

Thick- 
ness 
(Feet) 

Character  of 
Topography  and  Soil 

Cretaceous. 

• 

Upper  Cretaceous. 

Montana  . 

Fox  Hills 
sandstone. 

Friable  sandstone  and 
sandy  shale. 

Rolling    hills   and 
rounded  ridges  ;sandy 
soil  with  good  grass. 

Pierre  shale. 

Dark  shale  with  cal- 
careous concretions. 

2,000 

Wide  plains  with  shal- 
low    valleys;     thin, 
clayey,  and  not  very 
fertile  soil,  support- 
ing   fair    growth    of 
grass. 

Colorado  . 

Niobrarashale. 

Gray  calcareous  shale. 

100 

Shale  slopes;  limy  soil. 

Carlile  shale. 

Gray  shale  with  oval 
concretions  and  thin 
sandstones. 

500 

Rolling  hills  with  thin 
clay  soil,  mostly  cov- 
ered with  grass. 

Greenhorn  for- 
mation. 

Shale  with  impure  con- 
cretionary limestone. 

175 

Small  bare  ridges. 

Graneros  shale. 

Black  shale  with  con- 
cretions. 

Hard  gray  shale  con- 
taining   many   fish 
scales  (Mowry  shale 
member)  . 
Sandstone,  oil  bearing. 
Black  shale  with  small 
concretions. 

1,245 

Wide  valleys  contain- 
ing extensive  allu- 
vial deposits. 
Shaly    ridges,    partly 
1     wooded. 

Valleys  with  clay  soil 
and  badlands. 

Dakota  sand- 
stone. 

Gray  to  buff  sandstone, 
mostly  very  massive; 
weathers  reddish 
brown. 

50  + 

Plateaus,  canyons,  and 
high  cliffs  with  rocky 
slopes;    thin    sandy 
soil. 

Lower 
Cretaceous. 

Fuson  shale. 

Shale  and  sandy  shale 
with  local  sandstone. 

70 

Slopes   below   cliffs  of 
Dakota  sandstone. 

Lakota  sand- 
stone. 

Light-colored  coarse 
massive  sandstone. 

25-50 

Canyons     with     cliffs; 
thin  sandy  soil. 

o  3 

Morrison 
shale. 

Massive  pale  greenish- 
gray  to  maroon  shale 
with  limestone 
nodules. 

125  ± 

Steep  slopes  bel  ow  cliffs 
of  Lakota  sandstone; 
poor  soil. 

Newcastle. — The  Newcastle  field1  is  about  50  miles  southeast 
of  Moorcroft.  The  Graneros  shale,  which  contains  sandstone 
lenses,  crops  out  in  the  district,  and  in  places  a  heavy  paraffin  oil 
exudes  from  the  sands.  Drilling  had  not  revealed  commercial 
supplies  of  petroleum  until  1920,  when 'a  heavily  producing  well 
was  drilled. 

ANIGHT,  W.  C.,  and  SLOSSON,  E.  E. :  The  Newcastle  Oil  Field.  Wyoming 
Univ.  School  of  Mines  Pet.  Series,  Bull.  5,  1902. 


394  GEOLOGY  OF  PETROLEUM 

Upton-Thornton  Oil  Field.— The  Upton-Thornton  oil  field1  is  in 
Weston  and  Crook  Counties,  eastern  Wyoming.  The  rocks  out- 
cropping are  of  Cretaceous  age  and  lie  on  the  southwest  flank  of  the 
Black  Hills  Uplift.  An  anticline  strikes  northwest  through  the 
district,  and  on  its  crest  two  domes  are  developed.  One  of  them 
lies  near  Upton  and  the  other  about  a  mile  southwest  of  Thornton. 
Neither  of  these  domes  produces  oil.  About  three  miles  north- 
west of  Thornton  a  small  oil  field  is  developed  on  a  monocline  that 
dips  southwest  and  which  lies  west  of  the  anticline  on  which  the 
domes  are  located. 

The  oil  has  accumulated  on  or  near  a  terrace-like  slope  where 
the  dip  of  the  monocline  changes  (Fig.  164).  The  oil  occurs  in 
the  sandy  members  of  the  Colorado  shale,  one  horizon  being  in  the 
Graneros,  another  in  the  Carlile  shale.  The  oil  is  obtained  mainly 
from  a  sand  which  ranges  in  thickness  from  29  to  47  feet  and  is 
reached  at  depths  ranging  from  448  to  843  feet.  The  oil  near 
Thornton  is  light  green  in  color  and  of  light  gravity.  Northwest 
of  the  center  of  the  dome,  in  sec.  4,  T.  48  N.,  R.  66  W.,  several 
wells  have  been  sunk  to  depths  between  480  and  880  feet.  These 
yield  each  from  5  to  10  barrels  of  light  oil  daily. 2  The  wells  are 
on  a  structural  terrace,  and  the  productive  sand  crops  out  within 
half  a  mile  of  the  nearest  producing  well. 

Buck  Creek. — About  20  miles  north  of  Lusk,  near  the  center  of 
Niobrara  County, 3  there  is  a  well-defined  structural  terrace,  which 
Trumbull  designates  the  Buck  Creek  field.  The  beds,  which  lie 
flat  in  the  western  part  of  the  area,  dip  steeply  eastward  east  of 
Buck  Creek.  In  this  region  oil  is  said  to  be  obtained  from  the 
Muddy  sand  a  short  distance  below  the  Mowry. 

Mule  Creek. — The  Mule  Creek  oil  field  is  in  eastern  Wyoming, 
four  miles  from  the  South  Dakota  line,  about  35  miles  northeast 
of  the  Lande  Creek  field.  About  10  wells  sunk  on  an  anticline 
tested  125  to  150  barrels  of  high  grade  oil  daily  in  the  autumn  of 
1919.  The  oil  occurs  in  the  Dakota  sandstone  of  Cretaceous  age, 

HANCOCK,  E.  T.:  The  Upton-Thornton  Oil  Field,  Wyoming.  U.  S.  Geol. 
Survey  Bull.  716-B,  pp.  17-34,  1920. 

HANCOCK,  E.  T. :  The  Upton-Thornton  Oil  Field,  Wyoming.  U.  S.  Geol. 
Survey  Bull  716,  p.  31,  1920. 

'TRUMBULL,  L.  W.:  Prospective  Oil  Fields.  Wyoming  State  Geologist's 
Office  Bull.  5,  p.  8,  1913. 


ROCKY  MOUNTAIN  FIELDS  395 

SECTION  OP  ROCK  FORMATIONS  IN  THE  UPTON-THORNTON  FIELD 


System 

Series 

Group 

Formation  and 
Member 

Character 

Thick- 
ness 
(Feet) 

Cretaceous. 

Upper  Cre- 
taceous. 

Montana. 

Pierre  shale. 

Dark  shale  including  a  zone 
of  calcareous  concretions 
near  middle  and  a  few  thin 
beds  of  bentonite.  Only 
lower  1,200  feet  to  top  of 
zone  of  calcareous  concre- 
tions is  mapped. 

2,500* 

200 

700 

Colorado. 

Niobrara  shale. 

Chiefly  light-yellowish  to 
crearn-colored  calcareous 
shale,  with  some  impure 
chalk,  clay,  and  sand. 

Carlile  shale. 

Dark  shale  with  thin  beds 
of  soft  sandstone  mainly 
near  the  base. 

Greenhorn   lime- 
stone. 

Impure,  slabby  limestone. 

50 

Graneros  shale. 

Dark-gray  to  black  shale, 
including  many  large  cal- 
careous concretions,  espe- 
cially in  the  upper  part. 

800 

Mo  wry  shale 
member. 

Hard,  light-gray,  sandy 
shales  containing  numer- 
ous fish  scales.  Bentonite 
beds  near  the  top  and  to 
some  extent  near  the  base. 

150 

Dark,  sandy  shale  grading 
upwardintotypicalMowry 
shale. 

50 

Reddish  to  light-yellow  sand- 
stone associated  with  black 
carbonaceous  shale. 

3  to  15 

Dark-gray  to  black  shale. 

225 

Dakota  sandstone. 

Thin-bedded  to  massive  hard 
buff  sandstone. 

60 

Lower  Cre- 
taceous. 

Fuson  formation. 

Shale  and  thin-bedded  sand- 
stone. . 

20 

Lakota  sandstone. 

Sandstone,  in  part  conglom- 
eratic, with  some  coal  beds 
near  the  base. 

200 

Cretaceous(V). 

(?) 

Morrison  formation. 

Light-gray  to  pinkish  shale. 

130 

Jurassic. 

Upper    Ju- 
rassic. 

Sundance  formation. 

Light-gray  to  dark  greenish- 
gray  and  pinkish,  sandy 
shale  with  a  25-ft.  Band- 
stone  near  the  base. 

346 
492 

Triassic  (?). 

Spearfish  formation. 

Gypsum  and  red  clay  beds 
in  alternating  succession. 
Popularly  known  as  the 
"Red  Beds." 

Carboniferous. 

Permian 
(?). 

Minnekahta   lime- 
stone. 

Light-gray  to  pinkish  or 
purplish  limestone. 

34 

Opeche  formation. 

Red,  sandy  clay,  purplish  at 
the  top. 

74 

Pennsyl- 

vanian. 

Minnelusa   sand- 
stone. 

Light  gray  to  buff  calcareous 
sandstone. 

851 

Mississip- 
pian. 

Pahasapa  limestone  . 

White,  pale-buff,  pinkish, 
and  gray  limestone. 

398* 

396 


GEOLOGY  OF  PETROLEUM 


which  lies  about  1,400  feet  deep.  The  Minnelusa  sandstone  (Car- 
boniferous) which  contains  oil  in  the  Old  Woman  anticline  15  miles 
away,  is  expected  at  a  depth  of  2,700  feet  at  Mule  Creek  wells.1 


1! 


§ 


Spring  Valley.— The  Spring  Valley  field,  2 
Uinta  County,  southwestern  Wyoming,  is  an 
area  of  Mesozoic  and  later  sedimentary  rocks 
deformed  by  faulting  and  folding.  The  oil 
field  is  in  the  Absaroka  fault  zone,  which  is 
marked  by  reverse  faulting.  Numerous  oil 
springs  are  found  in  this  region,  among  them 
the  Brigham  Young,  Carter,  and  White 
springs,  which  occur  along  a  secondary  fault 
east  of  the  main  Absaroka  fault.  The  Aspen 
tunnel  of  the  Union  Pacific  Railroad,  which 
was  driven  through  the  Cretaceous  Frontier 
formation,  crossed  a  secondary  fault  in  the 
Absaroka  fault  zone,  and  at  the  fault  there 
was  a  considerable  seep  of  oil.  Many  wells 
put  down  in  this  region  found  some  oil,  but 
not  in  paying  quantities.  The  region  is  com- 
plexly deformed.  At  Hilliard  the  strata  are 
overturned.  Most  of  the  oil  found  in  the 
Spring  Valley  wells  comes  from  sandy  layers 
in  the  Aspen  shale.  The  oil-bearing  beds 
carry  little  water. 

Labarge. — The  Labarge  field3  is  in  Lincoln 
County,  about  80  miles  north  of  the  Spring 
Valley  field.  The  county  is  an  area  of  faulted 
and  folded  strata  of  Cretaceous  and  Tertiary- 
age.  The  dominant  structural  feature  is  the 
Absaroka  fault  zone.  In  the  vicinity  of 

!HANCOCK,  E  T  :  U.  S.  Geol.  Survey  Bull.  716-C. 
Press  Bull.  U.  S.  Geol.  Survey  No.  455,  August,  1920. 

2VEATCH,  A.  C.:  Geography  and  Geology  of 
Southwestern  Wyoming.  U.  S.  Geol.  Survey  Prof. 
Paper  56,  p.  139,  1907. 

3ScnuLTZ,  A.  R. :  The  Labarge  Oil  Field,  Central 
Uinta  County,  Wyoming.  U.  S.  Geol.  Survey  Bull. 
340,  p.  364,  1907. 


ROCKY  MOUNTAIN  FIELDS  397 

Labarge  Ridge  the  oil  formation  is  the  Aspen  (Mowry?),  a  division 
of  the  Colorado  that  consists  of  shale,  sandstone,  and  limestone. 
Oil  is  supposed  to  have  seeped  from  the  deep-lying  Aspen  under 
the  outcropping  Tertiary  beds.  In  a  sketch  of  this  field  Trumbull1 
shows  an  anticline  in  the  Cretaceous  which  includes  the  Aspen, 
overlain  by  the  flat-lying  Tertiary  beds. 

Big  Horn  Basin. — The  Big  Horn  Basin2  is  a  depression  nearly 
surrounded  by  high  mountain  ranges.  On  the  east  lie  the  Big 
Horn  Mountains,  on  the  south  the  Owl  Creek  and  Bridger  ranges, 
and  on  the  west  the  Shoshone  Mountains  (Fig.  165).  The  struc- 
ture of  the  northeastern  part  has  been  described  by  Washburne, 
and  that  of  the  southern  part  by  Hewett  and  Lupton. 

The  rocks  dip  from  the  mountains  toward  the  center  of  the  basin, 
where  the"  older  formations  are  deeply  buried.  The  Big  Horn 
Basin  may  be  separated  into  two  parts — an  inner  or  central  part, 
in  which  the  surface  rocks  belonging  to  the  Wasatch  and  younger 
formations  are  almost  horizontal,  and  an  outer  or  border  part 
adjacent  to  the  mountains,  in  which  the  beds  older  than  the 
Wasatch  are  thrown  into  small  folds.  The  Wasatch  and  younger 
beds  of  the  central  part  are  only  locally  horizontal,  however,  for 
they  dip  slightly  toward  the  middle  trough,  which  trends  roughly 
N.  40°  W. 

Near  the  mountains  there  are  two  almost  completely  circular 
chains  of  anticlines  and  domes,  one  inside  the  other  (Figs.  166, 
167).  The  inner  circle  has  yielded  almost  the  entire  production 
of  the  area.  All  of  the  producing  folds  are  elongated  domes,  or 

TRUMBULL,  L.  W. :  Wyoming  State  Geologist's  Office  Bull.  5,  p.  13, 1913. 

2HEWETT,  D.  F.,  and  LUPTON,  C.  T. :  Anticlines  in  the  Southern  Part  of  the 
Big  Horn  Basin,  Wyoming.  U.  S.  Geol.  Survey  Bull.  656,  1917. 

HINTZE,  F.  F.,  JR.  :  The  Basin  and  Gray  Bull  Oil  and  Gas  Fields,  Wyoming. 
Wyoming  State  Geologist's  Office  Bull.  10,  1914. 

DARTON,  N.  H.:  Mineral  Resources  of  the  Big  Horn  Mountain  Region. 
U.  S.  Geol.  Survey  Bull.  285,  pp.  303-310,  1906. 

FISHER,  C.  A.:  Geology  and  Water  Resources  of  the  Big  Horn  Basin, 
Wyoming.  U.  S.  Geol.  Survey  Prof.  Paper  53,  1906. 

WASHBURNE,  C.  W. :  Gas  Fields  of  the  Big  Horn  Basin,  Wyoming.  U.  S. 
Geol.  Survey  Bull.  340,  pp.  348-363,  1908. 

HEWETT,  D.  F. :  The  Shoshone  River  Section,  Wyoming.  U.  S.  Geol.  Sur- 
vey Bull.  541,  pp.  89-113,  1912. 

SCHULTZ,  A.  R. :  Geology  and  Geography  of  a  Portion  of  Lincoln  County, 
Wyoming.  U.  S.  Geol.  Survey  Bull.  543,  1914. 


398 


GEOLOGY  OF  PETROLEUM 


anticlines  plunging  at  both  ends.  Their  axes  are  rudely  parallel  to 
the  axes  of  the  mountain  ranges,  which  almost  encircle  the  basin. 
The  domes  and  anticlines  have  large  closures;  that  of  the  Grass 
Creek  anticline,  the  most  productive  in  the  basin,  is  over  2,000 
feet.  Many  of  the  oil-bearing  folds  are  faulted,  but  moderate 
amounts  of  faulting  do  not  seem  to  influence  accumulation 
adversely  in  this  region.  For  a  productive  region  that  is  so  much 


FIG.  165. — Sketch  map  showing  Big  Horn  Basin,  Wyoming. 


faulted,  surface  indications  of  oil  are  not  numerous,  although  oil 
seeps  have  been  found  on  or  near  the  Bonanza,  Sherard,  and  Lysite 
Mountain  anticlines,  and  near  the  base  of  the  Chugwater  forma- 
tion on  the  Red  Spring  anticline.  The  oil-bearing  strata  are  all  or 
nearly  all  marine.  Salt  water  is  found  in  many  of  the  folds,  but 
in  some  of  them  it  is  not  very  salty.  The  water  below  the  oil  on 
both  limbs  of  the  Grass  Creek  anticline  is  neither  sulphurous  nor 


ROCKY  MOUNTAIN  FIELDS 


399 


FORMATIONS  OF  Bio  HORN  BASIN,  WYOMING 
(After  Hewett  and  Lupton) 


System 

Formation 

Thickness 

(Feet) 

Character  of  Rocks 

Quaternary. 

Alluvium. 

Hot-spring  deposits. 
Terrace  gravels. 

0-50 

Valley    and    flood-plain    deposits    along 
streams. 
Local  deposits  of  calcareous  tufa. 
Gravels  and  boulders  washed  from  adja- 
cent mountains. 

0-30 

Tertiary. 

Volcanic  rock. 

(?) 

Andesitic  tuffs  and  flows  on  west  side  of 
basin. 

Wasatch. 

1,300  + 

Red  and  drab  clay;  buff  and  white  sand- 
stone with  gravel  lenses.  Many  areas  of 
badlands  around  border  of  basin. 

Fort  Union. 

2  ,000-5  ,600 

Buff  and  white  gritty  sandstone,  with  drab, 
red,  and  green  clay  ;  lenses  of  gravel  and 
lenticular  beds  of  coal. 

Tertiary  (?). 

Lance. 

840-1  ,800 

Buff  and  drab  sandstone  with  drab  and 
green  shale.  No  red  shale  or  coal  beds. 

Cretaceous. 

Montana. 
Colorado. 

Meeteetse. 
Mesaverde. 

250-1  ,400 

Soft  gray  and  brown  shale;  gray  and  buff 
sandstone  and  lenticular  beds  of  coal. 

1  ,120-1  ,410 

Buff  and  white  sandstone,  gray  and  brown 
shale  and  lenticular  beds  of  coal  near 
base. 

Cody. 

1  ,900-3  ,400 

Gray,  green,  and  black  shale,  with  cal- 
careous concretions  near  base,  merging 
with  buff  sandstone  at  top.  No  per- 
sistent sharply  marked  beds. 

Frontier. 

494-648 

West  side:  Seven  or  more  beds  of  gray  and 
buff  sandstone   with  gray  and  brown 
shale  and  bentonite. 
East  side:  Two  to  six  or  more  beds  of  sand- 
stone. 

Mo  wry. 

160-375 

Hard  gray  shale  containing  fish  scales 
with  Tenses  of  gravel-bearing  sandstone. 

Thermop- 
olis. 

400-800 

Gray  to  black  shale  with  one  persistent 
sandstone,  the  Muddy  sand  of  the 
drillers. 

Cloverly. 

110-300 

Two  beds  of  massive  buff  sandstone  sep- 
arated by  gray  or  variegated  shale. 
Upper  sand  is  the  Greybull. 

Cretaceous  (?)  . 

Morrison. 

150-580 

Purplish  and  pale  greenish-gray  shales  with 
sandstones  interbedded. 

Jurassic. 

Sundance. 

250-530 

Greenish-gray  sandstones  and  shales  with 
a  little  limestone  interbedded. 

Triassic. 

Chugwater. 

700-1  ,100 

Red  Beds:  Red  sandstones  and  shales  with 
a  thick  bed  of  gypsum  near  top. 

Carboniferous. 

Embar. 

250-480 

Gray  limestone,  with  gray  and  red  sandy 
shale  and  gypsum  interbedded.  Lime- 
stone very  thin  on  east  side  of  basin. 

Tensleep. 

30-230 

Massive  gray  sandstone,  containing  thin 
layers  of  limestone. 

Amsden. 

150-200 

Red  sandy  shales  and  sandstones,  with 
layers  of  limestone  and  chert. 

Madison. 

600-1  ,000 

Gray  massive  limestones. 

Ordovician. 

Bighorn. 

150-300 

Siliceous  gray  limestone,  very  hard  and 
massive. 

Cambrian. 

Deadwood. 

700-900 

Sandstone,  shale,  conglomerate,  and  lime- 
stone. 

400 


GEOLOGY  OF  PETROLEUM 


FIG.  166. — Geologic  map  of  southern  part  of  Big  Horn  Basin,  Wyoming. 
For  section  along  line  AB,  see  Fig.  167.  Numbers  refer  to  descriptions  in  table 
on  opposite  page  and  page  following.  (After  Hewett  and  Lupton.) 


ROCKY  MOUNTAIN  FIELDS 


401 


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402 


GEOLOGY  OF  PETROLEUM 


ANTICLINES  AND  DOMES  IN  THE  SOUTH  HALF  OF  THE  BIG  HORN  BASIN,  WYOMING  (1917)  —  Concluded 

till 
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ROCKY  MOUNTAIN  FIELDS 


403 


very  salty,  but  is  somewhat  alkaline.  Pre- 
sumably the  surface  water  has  entered  the  oil- 
bearing  sands  down  the  dips  of  the  beds  and 
along  faults  and  either  diluted  the  water  that 
had  been  stored  in  the  sands  or  swept  it  out. 

The  beds  that  have  yielded  most  of  the  oil 
and  gas  are  of  Cretaceous  age  and  are  parts  of 
the  Cleverly  formation,  Thermopolis  shale, 
Mowry  shale,  and  Frontier  formation.  Gas  is 
reported  also  from  a  sand  in  the  Morrison 
formation  on  the  Shoshone  anticline  near  Cody. 
It  is  uncertain  whether  any  of  the  beds  lower 
than  the  Cleverly  formation  will  prove  to  be 
important  sources  of  oil  or  gas.  Only  one  well 
(on  the  Nieber  anticline,  has  tested,  under 
favorable  structural  conditions,  beds  higher 
than  the  Cody  shale,  which  overlies  the  Fron- 
tier formation.  The  prospect  that  any  of  these 
higher  beds  will  yield  important  quantities  of 
either  oil  or  gas,  according  to  Hewett  and  Lup- 
ton,  is  uncertain. 

The  sands  of  the  Frontier  formation  yield  the 
greatest  part  of  the  oil,  and  the  sands  of  the 
Mowry  shale  and  the  Greybull  sand  yield  oil  as 
well  as  most  of  the  gas  now  produced  in  the 
basin.  Where  synclines  or  beds  lying  flat  have 
been  drilled  they  have  struck  little  oil  or  gas  or 
none. 

In  the  three  most  productive  fields  in  the 
area — the  Greybull,  Torchlight,  and  Grass 
Creek — the  zone  in  the  prolific  sands  that  yields 
the  oil  extends  much  lower  along  a  part  of  the 
flat  basinward  limb  of  the  fold  than  on  the  steep 
mountain  ward  limb.  Thus  at  Grass  Creek  the 
sands  are  prolific  at  a  lower  altitude  in  the 
southeastern  part  of  the  field  than  in  the  south- 
western or  western  part.  As  stated  by  Hewett 
and  Lupton,  every  tested  field  in  the  Big  Horn 
Basin  which  has  yielded  appreciable  quantities 
of  oil  and  gas  lies  toward  the  principal  trough  of 


iii  « 

M     3      S  S 


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18 


+  I 


404 


GEOLOGY  OF  PETROLEUM 


the  basin,  and  every  tested  upfold  which  is  separated  from 'this 
trough  by  other  folds  has  either  yielded  water  and  the  merest 
traces  of  oil  and  gas  or  is  barren.  The  side  of  the  anticline  or 
elongated  dome  that  is  more  nearly  flat  is  in  general  more  pro- 


Structure  contours  (lines  of  equal  altitude)  on  top  of 

Greybull  sand.  Numbers  show  distance  above  #Gas  well 

sea  level.    Contour  interval^  200  feet  ^Dry  hofe 

FIG.  168. — Structure  contour  map  and  section  of  Greybull  dome,  Wyoming. 
(After  Heivett  and  Lupton.} 

ductive  than  the  steeply  plunging  side.     The  flatter  dips  are 
generally  toward  the  basin,  from  which  the  accumulations  came. 

The  Elk  Basin  pool,  in  the  northern  part  of  the  oil  district,  is  on 
the  boundary  between  Wyoming  and  Montana.     Structurally  the 


ROCKY  MOUNTAIN  FIELDS  405 

field  is  a  dome  cut  by  cross  faults.  The  oil  is  of  light  gravity  and 
comes  from  sandstone  of  the  Frontier  formation. 

The  Byron  dome,  which  lies  southeast  of  Elk  Basin,  produces 
light  oil  that  is  refined  at  Cowley,  near  by.  The  productive  sands 
are  the  Frontier,  Mowry,  and  Morrison  (?). 

Greybull  is  southeast  of  Byron.  It  produces  a  high-grade  par- 
affin-base oil  and  much  gas.  The  Greybull  sand  is  the  upper  sand 
in  the  Cleverly  formation.  Gas  is  found  in  the  top  of  the  dome, 
and  oil  lower  down  on  the  west  and  northwest  sides  (Fig.  168). 
Its  accumulation  there  may  be  due  in  part  to  the  presence  of  water 
in  the  Greybull  sand  close  to  the  gas  wells  on  the  north,  east  and 
southeast  sides,  the  water  having  pushed  the  oil  toward  the  west 
and  northwest.  Water  can  easily  enter  the  oil  and  gas  sand  at  its 
outcrop  around  the  south  end  of  Sheep  Mountain,  3  to  4  miles 
north  of  the  Greybull  dome. 

The  Torchlight  dome  (Fig.  169),  also  termed  the  Basin  dome,  is 
only  about  10  miles  southeast  of  the  Greybull  dome  and  2  or  3 
miles  east  of  the  town  of  Basin.  It  is  an  elliptical  upfold  in  the 
rocks  trending  northwest,  with  its  broad  end  facing  southeast.  It 
is  about  3  miles  long  and  2  miles  wide  and  is  separated  from  the 
Lamb  anticline  by  a  shallow  syncline,  a  depression  in  the  rocks 
200  to  300  feet  deep.  Along  the  crest  of  the  dome  the  beds  lie 
nearly  flat,  dipping  gently  outward.  On  the  north  limb  the  maxi- 
mum dip  of  the  rocks  (11°)  is  reached  about  a  quarter  of  a  mile 
away  from  the  crest  line;  beyond  this  the  beds  gradually  flatten  to 
the  axis  of  the  syncline.  The  dips  are  comparatively  low,  averag- 
ing 3°  to  4°  at  the  northwest  and  southeast  ends  of  the  dome. 
The  rocks  at  the  surface  in  the  center  of  the  Torchlight  dome 
belong  to  the  upper  part  of  the  Frontier  formation,  which  in  this 
locality  is  a  little  more  than  550  feet  thick.  A  prominent  sand- 
stone (the  Torchlight)  of  this  formation  encircles  the  central  part 
of  the  dome  in  a  line  of  cliffs.  A  thicker  and  more  prominent  sand- 
stone, the  Peay,  in  the  lower  part  of  the  Frontier  formation,  is  not 
exposed  in  this  dome  but  is  well  shown  along  Big  Horn  River 
near  Greybull.  'Directly  under  the  Frontier  formation  is  the 
Mowry  shale,  which  contains  two  sand's — the  Kimball  and  Octh 
Louie — that  yield  oil.  The  entire  formation  yields  some  oil. 
Under  the  Mowry  shale  is  the  Thermopolis  shale,  about  700  feet 
thick;  the  Muddy  sand,  which  contains  a  little  gas  in  some  wells, 
is  about  300  feet  above  its  base.  Directly  beneath  the  Thermo- 


406  GEOLOGY  OF  PETROLEUM 

polls  shale  is  the  Cleverly  formation,  about  125  feet  thick,  the  top 


distance  above  or  below 
sea  level    Contour  inter. 

val.    200 'feet 


FIG.'  169. — Contour  map  and  cross  section  of  Lamb  anticline  and  Torchlight 
dome,  Bighorn  Basin,  Wyoming.  Numbers  with  symbols  refer  to  descriptions 
in  U.  S.  Geol.  Survey  Bull.  656.  (After  Lupton.} 

sandstone  of  which  is  about  20  feet  thick  and  is  known  as  the 


ROCKY  MOUNTAIN  FIELDS  407 

Grey  bull  sand.  In  the  Grey  bull  field1  this  bed  of  sand  yields 
nearly  all  the  oil  and  gas. 

The  Bonanza  dome  is  about  18  miles  southeast  of  Torchlight. 
Oil  seeps  from  a  sand  in  the  Mowry  shale  exposed  near  the  crest  of 
the  dome,  and  the  oil  was  used  by  early  settlers.  The  Thermopolis 
shale  is  exposed  on  the  crest.  The  dome  has  yielded  little  or 
no  oil.2 

The  Warm  Springs  dome,  southwest  of  Bonanza,  on  the  opposite 
side  of  the  basin,  yields  oil. 

The  Grass  Creek  anticline,3  about  28  miles  northwest  of  Ther- 
mopolis, is  the  most  productive  fold  in  the  Big  Horn  basin.  It 
plunges  at  both  ends,  giving  ample  closure.  In  three  wells  oil 
flowed  over  the  casing,  but  none  of  the  wells  were  strong  gushers. 
Although  most  of  the  wells  are  pumped  they  have  a  long  life.  The 
water  below  the  oil  is  not  salty  but  is  said  to  be  alkaline.  The 
outcropping  rock  is  the  Cody  shale.  The  sandstones  of  the 
Frontier  formation  which  yield  the  oil  in  this  anticline  do  not  out- 
crop but  are  struck  in  wells  at  a  minimum  depth  of  365  feet. 

The  contours  show  a  relatively  simple  but  sharp  anticline  broken 
by  a  few  faults.  The  fold  is  unsymmetrical,  with  a  steep  limb  on 
the  southwest  wide  and  a  very  gently  dipping  limb  on  the  north- 
east side.  The  dips  on  the  northeast  side  increase  from  zero  at  the 
crest  line  to  a  maximum  of  34°  on  the  outcrop  of  beds  of  the 
Meeteetse  formation,  4  miles  distant.  The  rim  rock  of  Mesaverde 
sandstone  dips  from  12°  to  24°  along  the  northeast  limb.  On  the 
southwest  side  the  beds  descend  sharply  into  the  adjacent  syncline 
and  dip  from  50°  to  60°  across  a  wide  belt.  The  anticline  is 
limited  on  the  northwest  by  a  short  syncline,  west  of  which  is  the 
Little  Grass  Creek  dome. 

;>  The  Buffalo  Basin  anticline  is  about  10  miles  northwest  of  the 
Grass  Creek  field.  The  Cody  shale  crops  out,  and  gas  is  found  in 
the  sands  of  the  Frontier. 

The  Oregon  Basin  field  is  about  20  miles  northwest  of  the  Buffalo 
Basin  field.  It  produces  gas  from  sands  below  the  Frontier. 

The  Cody  field  is  northwest  of  the  Oregon  Basin  field  and  pro- 
duces some  gas  and  a  little  light  oil  from  sands  below  the  Frontier. 


,  D.  F.,  and  LUPTON,  C.  T.  :  Op.  cit.,  pp.  76-77. 
*Idem,  p.  93. 
3Idem,  p.  153. 


408  GEOLOGY  OF  PETROLEUM 

References  for  Wyoming 

BARNETT,  V.  H.:  The  Douglas  Oil  Field,  Converse  County,  Wyoming. 
U.  S.  Geol.  Survey  Bull  541,  pp.  49-88,  1914. 

—    The  Moorcroft  Oil  Field,   Crook  County,   Wyoming.     U.   S. 
Geol.  Survey  Bull  581,  pp.  83-104,  1915. 

Possibilities  of  Oil  and  Gas  in  the  Big  Muddy  Dome,  Converse 

and  Natrona  Counties,  Wyoming.     U.  S.  Geol.  Survey  Bull.  581,  pp.  105- 
117,  1915. 

DARTON,  N.  H. :  Preliminary  Report  on  the  Geology  and  Underground 
Water  Resources  of  the  Central  Great  Plains.  U.  S.  Geol.  Survey  Prof.  Paper 
32,  1905. 

— Mineral  Resources  of  the  Big  Horn  Mountain  Region,  Wyoming. 

U.  S.  Geol.  Survey  Butt.  285,  pp.  303-310,  1906. 

and  SIEBENTHAL,  C.  E. :  Geology  and  Mineral  Resources  of  the 

Laramie  Basin,  Wyoming.     U.  S.  Geol.  Survey  Bull.  364,  1909. 

FISHER,  C.  A. :  Geology  and  Water  Resources  of  the  Big  Horn  Basin,  Wyom- 
ing. U.  S.  Geol.  Survey  Prof.  Paper  53,  pp.  1-72,  1906. 

Mineral  Resources  of  the  Big  Horn  Basin,  Wyoming.     U.  S. 

Geol.  Survey  Bull.  285,  pp.  311-315,  1906. 

HARES,  C.  J. :  Anticlines  in  Central  Wyoming.  U.  S.  Geol.  Survey  Bull. 
641,  pp.  233-279,  1917. 

HEWETT,  D.  F. :  The  Shoshone  River  Section,  Wyoming.  U.  S.  Geol.  Sur- 
vey Bull.  541,  pp.  89-113,  1914. 

and  LUPTON,  C.  T. :  Anticlines  in  the  Southern  Part  of  the  Big 

Horn  Basin,  Wyoming.     U.  S.  Geol.  Survey  Butt.  656,  1917. 

HINTZE,  F.  F. :  The  Basin  and  Greybull  Oil  and  Gas  Fields,  Wyoming. 
Wyoming  State  Geologist's  Office  Bull.  10,  1915. 

JAMISON,  C.  E. :  The  Douglas  Oil  Fields,  Converse  County,  Wyoming;  The 
Muddy  Creek  Oil  Field,  Carbon  County,  Wyoming.  Wyoming  State  Geol- 
ogist, ser.  B.,  Bull.  3,  1912. 

KNIGHT,  W.  C. :  A  Preliminary  Report  on  the  Artesian  Basins  of  Wyoming. 
Wyoming  Univ.  Exper.  Sta.  Butt.  45,  1900. 

and  SLOSSON,  E.  E. :  The  Dutton,  Rattlesnake,  Oil  Mountain, 

and  Powder  River  Oil  Fields.     Wyoming  Univ.  School  of  Mines  Pet.  Ser., 
Butt.  4,  1901. 

The  Newcastle  Oil  Field.     Wyoming  Univ.  School  of  Mines 

Pet.  Ser.,  Butt.  5,  1902. 

LUPTON,  C.  T. :  Oil  and  Gas  Near  Basin,  Big  Horn  County,  Wyoming. 
U.  S.  Geol.  Survey  Bull.  621,  pp.  157-190,  1916. 

SCHULTZ,  A.  R. :  The  Labarge  Oil  Field,  Central  Uinta  County,  Wyoming. 
U.  S.  Geol.  Survey  B-utt.  340,  pp.  364-373,  1908. 

Geology  and  Geography  of  a  Portion  of  Lincoln  County,  Wyom- 
ing. U.  S.  Geol.  Survey  Butt.  543,  pp.  1-141,  1914. 

TRUMBULL,  L.  W. :  Light  Oil  Fields  of  Wyoming.  Wyoming  State  Geol- 
ogist's Office  Butt.  12,  1916. 

Prospective  Oil  Fields.     Wyoming  State  Geologist's  Office  Butt. 

5,  1913. 


ROCKY  MOUNTAIN  FIELDS  409 

VEATCH,  A.  C. :  Geography  and  Geology  of  a  Portion  of  Southwestern 
Wyoming,  with  Special  Reference  to  Coal  and  Oil.  U.  S.  Geol.  Survey  Prof. 
Paper  56,  1907. 

Coal  and  Oil  in  Southern  Uinta  County,  Wyoming.     U.  S.  Geol. 

Survey  Bull.  285,  pp.  331-335,  1906. 

Coal  Fields  in  East-Central  Carbon  County,  Wyoming.     U.  S. 

Geol.  Survey  Bull.  316,  pp.  244-260,  1907. 

WASHBURNE,  C.  W. :  Gas  Fields  of  the  Big  Horn  Basin,  Wyoming.  U.  S. 
Geol.  Survey  Bull.  340,  pp.  348-363,  1908. 

WEGEMANN,  C.  H. :  The  Salt  Creek  Oil  Field,  Natrona  County,  Wyoming. 
U.  S.  Geol.  Survey  Butt.  452,  pp.  37-83,  1911. 

The  Powder  River  Oil  Field,  Wyoming.     U.  S.  Geol.  Survey 
Butt.  471,  pp.  56-75,  1912. 

The  Salt  Creek  Oil  Field,  Wyoming.     U  S.  Geol.  Survey  Butt. 
670,  1917. 

WOODRUFF,  E.  G.:  The  Lander  Oil  Field,  Fremont  County,  Wyoming. 
U.  S.  Geol.  Survey  Butt.  452,  pp.  7-36,  1911. 

ZIEGLER,  VICTOR:  The  Pilot  Butte  Oil  Field,  Fremont  County,  Wyoming. 
Wyoming  State  Geologist's  Office  Bull.  13,  p.  143,  1916. 

Popular  Oil  Geology,  New  York,  Wiley  &  Sons,  1918. 

MONTANA 

General  Features. — The  Cretaceous  and  later  rocks  that  cover 
extensive  areas  in  Wyoming  are  present  in  force  also  in  Montana. 
The  mountain  areas  are  in  the  main  anticlinal,  and  as  a  rule  igneous 
and  metamorphosed  rocks  form  their  central  masses,  as  in  Wyom- 
ing. In  Montana,  however,  there  are  larger  and  more  numerous 
bodies  of  post-Cretaceous  igneous  rocks,  whereas  in  Wyoming  the 
larger  central  mountain  masses  were  formed  in  general  before  the 
Cretaceous  sediments  were  laid  down,  and  the  sedimentary  rocks 
rest  upon  the  eroded  igneous  bodies.  For  that  reason  Montana 
contains  more  numerous  metalliferous  veins,  which  are  associated 
with  the  great  post-Cretaceous  intrusive  rocks.  Such  veins  are 
very  sparingly  developed  in  Wyoming.  The  basin  areas  in  Mon- 
tana exhibit  minor  folds,  like  the  basin  areas  of  Wyoming,  espe- 
cially away  from  the  centers  of  the  basins  and  around  their  rims. 
Although  the  rocks  present  and  the  structure  are  favorable  for  oil 
and  gas  prospecting  in  Montana,  the  production  thus  far  is  very 
small.  Some  of  the  sands  are  tight.  The  State  has  not  been  fully 
prospected,  however,  and  there  are  reasons  for  supposing  that 
productive  oil  or  gas  fields  may  yet  be  discovered.  The  structure 
of  the  Big  Horn  Basin,  Wyoming,  extends  northwestward  into 
Montana.  The  outcrops  of  Cretaceous  rocks  expand  in  central 


410 


GEOLOGY  OF  PETROLEUM 


and  northern  Montana,  covering  broad  areas  between  the  Rocky 
Mountain  front  and  the  great  Tertiary  areas  in  the  eastern  part 
of  the  State  (Fig.  170).  Here  and  there  they  are  raised  around 
small  uplifts  of  older  rocks,  such  as  the  Judith  Mountains,  and 
Little  Rocky  Mountains,  and  other  outlying  ranges. 

Although  few  large  fields  have  been  discovered  in  Montana,  the 
Elk  Basin  oil  pool,  about  55  miles  south  and  a  little  west  of  Billings, 
lies  partly  in  Wyoming  and  partly  in  Montana.  The  portion  of 
this  field  lying  in  Montana  produced  44,917  barrels  of  oil  in  1917. 
Commercial  quantities  of  gas  have  been  found  very  near  Baker 
and  Glendive,  Dawson  County.  Two  oil  wells  were  brought  in 
in  Devil's  Basin,1  near  Roundup,  Montana,  in  1919.  One  of  them, 
the  Van  Duzen  well,  yielded  a  heavy  black  oil  of  23°  Baume.  In 


500(IS 


Wfes 


Illllll  Triassi'c  and  Juror$sl 


ED  Tertiary 


}  FIG.  170. — Geologic  sketch  map  of  Montana.  Silurian  and  Devonian  roc1: 
are  included  in  other  series. 

eastern  Fergus  County,  near  Mosby,  on  the  Cat  Creek  dome 
(Fig.  171),  several  wells  were  brought  in  in  1920  that  yielded  a  high 
gravity  oil.  One  of  these  was  reported  to  yield  over  1,000  barrels 
a  day. 

A  little  oil  was  found,  probably  in  the  Ellis  formation,  of  Jur- 
assic age,  in  the  Woman's  Pocket.  The  Kootenai  produces  the 
high  grade  oil  of  Cat  Creek  dome  and  is  generally  regarded  as  a 

1BowEN,  C.  F. :  Coal  Discovered  in  a  Reconnaissance  Survey  Between 
Musselshell  and  Judith,  Montana.  11.  S.  Geol.  Survey  Bull.  541,  part  2, 
pp.  328-337,  1914. 


ROCKY  MOUNTAIN  FIELDS 


411 


possible  producer  in  many  parts  of  the  area.  The  Kootenai1  con- 
sists of  an  upper  and  a  lower  sandstone  member  separated  and 
overlain  by  shale  that  is  generally  red.  It  is  in  general  about  500 
feet  thick  and  the  lower  sand  is  30  to  40  feet  thick.  The  upper 
sand  is  water  soaked  and  the  lower  one  is  oil  bearing. 

The  Colorado  shale,  about  1,800  feet  thick,  lies  above  the  Koot- 
enai. It  is  composed  of  black  shale  with  a  sandstone  member  at 
its  base.  In  north  central  Montana  it  shows  oil  seeps,  and  in 
Wyoming  it  produces  oil  in  the  Big  Horn  basin,  but  thus  far  (1919) 
has  not  proved  productive  in  Montana. 


I -Du,;  Creek  Structures 
2 -Arrow  Creek  Dome 
9-Sagtr  Canyon  Dome 
4-Garucill  Dome 
6  -Gilt  Edge  Domes 


6-Boxelder  Dome 
T- Brush  Cr«k  Dome 
8 -Cat  Creek  Dome 
9  -Button  Buttc  Eoire 
10 -Devil's  Basin 


11  -Howard  Coulee 
12 -Big  Wall  Dome 
13 -Willow  Creek 
H  -Bole  Creek 


FIG.  171. — Sketch  of  Fergus  and  parts  of  adjoining  countries,  Montana,  show- 
ing position  of  domes,  oil  fields  and  prospects.   (After  Freeman.) 


Stillwater  Basin. — In  the  Upper  Stillwater  Basin,  southwest  of 
Billings  and  northwest  of  Red  Lodge,2  drill  holes  have  been  sunk 
for  oil  at  several  places.  The  rocks  in  this  area  range  from  the 
coal  measures  of  lower  Montana  (Upper  Cretaceous)  age  to  the 
Fort  Union  formation  (Eocene).  Older  sedimentary  formations 
and  crystalline  rocks  are  exposed  in  the  Beartooth  Mountains, 
along  whose  north  base  there  is  a  profound  fault  that  brings  Pale- 

^REEMAN,  O.  W. :  Oil  Fields  in  Central  Montana.  Eng.  and  Min.  Jour., 
vol.  109,  pp.  936-938,  1920. 

2CALVERT,  W.  R. :  Geology  of  the  Upper  Stillwater  Basin,  Stillwater  and 
Carbon  Counties,  Montana.  U.  S.  Geol.  Survey  Bull.  641,  pp.  199-214,  1917. 


412 


GEOLOGY  OF  PETROLEUM 


GEOLOGICAL  SECTION  IN  CENTRAL  MONTANA 

(After  Freeman0) 

Quaternary  (Travertine,  terrace  gravel,  alluvium,  glacial  drift). 
Tertiary  (Lance,  shale  and  sandstone,  700  to  800  feet). 

Feet 

Bearpaw  shale 1,100± 

Judith  River  forma- 
tion (sandstone  and 

Montana*!    shale) 250-500 

Claggett  shale 700  *= 

Eagle  sandstone. .  .  .    200-300 

Cretaceous  .  .  .  [Gas  sand  at  Havre 

Mesozoic Colorado  shale  with  thin  beds 

of   sandstone    (contains   gas, 

possibly  oil 1,800  =*= 

Kootenai  sandstone,  coal,  and 

shale  (lower  sand  oil  bearing)  ^    500  ± 
f  Morrison  shale  and  sandstone.  125  =*= 

Jurassic Elhsjoraiation,  shale  and  sand- 
stone (possibly  contains  oil) .  .  400  =*= 
Pennsylvania — Quadrant  shale  ^ 
Carboniferous      and  sa*ndstone  (oil  bearing) .    100-200 

Mississippian — Madison  lime- 
Paleozoic  stone 800 

Siluro-Devonian  limestone 300 

[Alternating  shale  and  limestone  500-700 
Cambrian .  ....  3  Flathead  quartzite  and  sand- 

(  stone 100 

(Algonkian — Belt  series — black  and  green  shale        1,000 
Pre-Cambrian  .  .  .  \  Archean — Gneisses    and    schists;    exposed    in 
I   Little  Belt  Mountains 


"FREEMAN,  O.  W.:  Op.  tit.,  p.  938. 

ozoic  rocks  into  contact  with  Tertiary  formations  south  of  Red 
Lodge  and  with  successively  older  strata  to  the  west.  Drilling 
in  1916  was  done  on  the  axis  of  an  anticline,  but  the  absence  of  oil 
in  the  rock  section  in  commercial  amounts,  according  to  Calvert, 
is  inconclusive,  because  the  holes  were  of  insufficient  depth  and 
because  they  were  put  down  on  the  pitching  end  of  the  anticline. 
The  absence  of  water  in  the  drill  holes,  however,  suggests  that  the 
beds  penetrated  are  not  charged  with  oil  higher  in  the  anticlinal 
arch.  If  oil  is  present  at  any  horizon  through  which  the  drill  has 
passed  it  has  accumulated  at  that  horizon  lower  down  on  the  flanks 
of  the  anticline. 

In  sec.  32,  T.  6  S.,  R.  18  E.,  according  to  Calvert,  there  is  more 
justification  for  prospecting.     Indications  of  oil  were  reported  in 


-ROCKY  MOUNTAIN  FIELDS 


413 


several  holes,  and  it  is  said  that  in  one  hole  small  amounts  of  oil 
were  obtained.  At  three  points  near  by  small  pools  of  asphalt 
occur.  These  pools  are  augmented  by  asphalt  oozing  from  the 
ground. 


LEGEND 


FIG.  172. — Geologic  sketch  or  key  map  showing  relation  of  Lake  Basin  field, 
Montana  to  major  structural  features  of  the  region.  (After  Willis,  Hancock 
and  others.) 

Lake  Basin. — The  Lake  Basin  field  is  northwest  of  Billings,  in 
south-central  Montana,  and  includes  portions  of  Sweet  Grass, 
Stillwater,  Musselshell,  and  Yellowstone  Counties.  The  rocks 
outcropping  in  this  region  (Fig.  172)  are  of  Cretaceous  and  Ter- 
tiary age.  The  formations  exposed  and  those  that  will  probably  be 
encountered  in  depth  are  as  follows: 


414 


GEOLOGY  OF  PETROLEUM 


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tion, as  a  whole,  presents  a  decidedly  light-gray 
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snerally  consists  of  a  lower  member  of  massive 
light-colored,  in  places  false-bedded  sandstone, 
a  middle  member  consisting  of  brown  andesitic 
beds,  and  an  upper  member  containing  abun- 
dant tufaceous  material. 

.uish  and  light  to  dark  grayish  marine  shale,  in- 
cluding lenses  and  fingers  of  sandstone  contain- 
ing numerous  plant  remains. 

2ds  of  soft,  massive  light-yellow  sandstone  inter- 
bedded with  layers  of  light  bluish-gray  to  black 
carbonaceous  shale,  including  an  occasional  thin 
seam  of  coal.  Many  of  the  beds  yield  numerous 
plant  remains. 

3lts  of  thin-bedded  sandstone  alternating  with 
those  consisting  mainly  of  soft,  sandy  shale. 

tiis  formation  includes  a  belt  of  thin-bedded  to 
massive  sandstone  at  the  top  and  a  massive, 
ledge-makingsandstone  from  50  to  100  feet  thick 
at  the  base.  The  upper  and  lower  sandstones  are 
separated  by  a  belt  of  softer  beds  including  sandy 
and  carbonaceous  shales  and  locally  thin  seams 
of  coal.  The  upper  sandstone  is  commonly 
capped  by  a  thin  layer  of  .black  chert  pebbles. 

amposed  mainly  of  light  to  dark  gray  shale,  in- 
cluding thin  layers  and  lenticular  beds  of  sand- 
stone. About  90  feet  below  the  base  of  the  Eagle 
sandstone  is  a  soft  sandstone  entirely  without 
bedding  planes  but  including  innumerable  small 
joint  planes.  This  sandstone  is  capped  by  a  thin 
layer  of  hard  brown  sandstone  separated  into 
rectangular  blocks  by  two  sets  of  parallel  joints. 

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ROCKY  MOUNTAIN  FIELDS  415 

There  are  in  the  field  two  dominating  folds — the  Big  Coulee- 
Hailstone  dome  and  the  northwest  end  of  the  Big  Horn  Mountain 
anticline.  The  Broadview  dome  is  a  local  uplift  about  7  miles 
southwest  of  Broadview. 

The  most  striking  feature  of  the  structure  of  the  Lake  Basin 
field  is  the  long,  narrow  belt  of  shearing  that  crosses  the  field  from 
the  northwest  corner  southeastward  about  8  miles  north  of  Billings. 
The  most  intense  shearing  occurred  along  the  steeply  dipping  south 
flank  of  the  Big  Coulee-Hailstone  dome  and  around  the  southeast 
side  of  the  Broadview  dome. 

In  this  field  surface  indications  of  petroleum  are  not  prominent. 
There  seems  to  be  no  evidence  of  oil  or  gas  having  escaped  along 
any  of  the  fault  planes,  but  it  is  difficult  to  ascertain  to  what  extent 
the  lower  sands  have  been  faulted.  It  appears  possible  that  well- 
defined  sandstones  such  as  those  present  in  most  of  the  productive 
Wyoming  fields  are  lacking  in  the  Lake  Basin  field.  It  may  be, 
however,  that  the  available  drill  records  fail  to  represent  the  true 
nature  of  the  Colorado  sands  and  that  future  drilling  will  establish 
the  existence  of  sandstones  under  parts  of  the  Lake  Basin  field 
similar  to  those  underlying  certain  portions  of  the  Musselshell 
Valley,  farther  north. 

The  Huntley  field,1  northeast  of  Billings,  is  in  Yellowstone  and 
Bighorn  Counties,  Montana,  just  east  of  Lake  Basin  field.  The 
rocks  are  of  Cretaceous  and  later  ages,  are  thrown  into  folds,  and 
are  faulted. 

The  Colorado  formations,  that  are  productive  in  Wyoming,  are 
under  cover  in  this  region.  There  are  no  pronounced  oil  seeps. 

Porcupine  Dome. — The  Porcupine  Dome,2  Rosebud  County, 
Montana,  lies  north  of  Forsyth  on  the  Chicago,  Milwaukee  & 
St.  Paul  Railway. 

The  formations  exposed  at  the  surface  in  this  area  extend  from 
the  Lance  formation  down  to  the  upper  part  of  the  Colorado  shale. 

The  dominant  structure  of  this  area  is  that  of  an  elongate, 
roughly  triangular  dome  whose  outline  is  indicated  by  the  inner 
margin  of  the  Judith  River  formation.  Within  that  margin  the 

HANCOCK,  E.  T. :  Geology  and  Oil  and  Gas  Prospects  of  the  Huntley 
Field,  Montana.  U.  S.  Geol.  Survey  Bull.  711-G,  pp.  105-148,  1920. 

2BowEN,  C.  F. :  Possibilities  of  Oil  in  the  Porcupine  Dome,  Rosebud  County, 
Montana.  U.  S.  Geol.  Survey  Bull.  621-F,  pp.  61-70,  1915. 


416 


GEOLOGY  OF  PETROLEUM 


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ROCKY  MOUNTAIN  FIELDS 


417 


GEOLOGIC  FORMATIONS  EXPOSED  IN  THE  PORCUPINE  DOME,  MONTANA 

(After  Bowen) 


System 

Group 

Formation 

Thickness, 
Feet 

Character 

Quaternary 

Alluvial  sand,  gravel,  and 
silt  along  Yellowstone 
and  Musselshell  rivers 
and  some  of  the  smaller 
streams. 

Tertiary  (?). 

Lance  forma- 
tion. 

Brown,  irregularly  bedded 
sandstone,  alternating 
with  "somber"  gray 
shale. 

Cretaceous. 

Montana. 

B  e  a  r  p  a  w 
shale. 

900-1,  000  * 

Dark,  gray  shale  in  which 
occur  calcareous  concre- 
tions containing  marine 
invertebrate  fossils. 

Judith  River 
formation. 

100-200* 

Upper  sandstone  member, 
light-brown  to  light- 
gray  massive  sandstone. 
Middle  member,  light- 
gray  to  dark-gray  shale. 
Lower  member,  sand- 
stone which  weathers 
brown  and  gives  rise  to 
large,  boulder-like 
masses.  The  formation 
is  of  fresh-water  origin 
in  the  western  part  of 
the  field  and  of  marine 
origin  in  the  eastern 
part. 

Claggett  anc 
Colorado 
shales. 

3,000 

Dark  gray  to  black  shale; 
upper  part  highly  plas- 
tic when  wet,  and  con- 
tains fossils  characteris- 
tic of  the  Claggett  for- 
mations; lower  part 
slightly  darker  in  color, 
more  fissile  and  less 
plastic  when  wet,  and 
contains  fossils  of  Colo- 
rado age. 

dome  has  a  maximum  north-south  diameter  of  about  33  miles  and 
a  maximum  east-west  diameter  of  27  miles.  Along  the  east  and 
north  sides  of  the  dome  the  Judith  River  formation  dips  away  from 
the  axis  of  uplift  at  angles  ranging  from  1°  to  8°,  the  steeper  dips 
being  on  the  east  side. 


418  GEOLOGY  OF  PETROLEUM 

No  oil  or  gas  seeps  are  known  in  this  region.  The  sandstones 
of  the  Judith  River  formation  are  not  probable  receptacles  of  oil 
or  gas,  as  these  sandstones  are  well  exposed  in  the  field  and  show 
no  indications  of  the  presence  of  any  bituminous  substance.  Oil  or 
gas,  according  to  Bowen,  may  or  may  not  occur  in  the  sandstones 
at  the  base  of  the  Colorado  and  in  the  underlying  Kootenai  (?). 
Elsewhere  sandstones  at  simlar  stratigraphic  positions  are  oil 
bearing. 

In  1920  oil  was  found  in  wells  near  Mosby  on  an  anticline  west 
of  the  Porcupine  dome. 

Musselshell  Valley. — The  Musselshell  Valley,1  about  midway 
between  Billings  and  Lewiston,  is  occupied  principally  by  Creta- 
ceous rocks,  with  subordinate  exposures  of  Tertiary  sediments  and 
of  igneous  rocks.  The  Cretaceous  rocks  are  folded  into  gentle 
anticlines  and  synclines.  Although  no  commercial  production  of 
oil  in  this  region  has  been  recorded,  the  region  is  regarded  by 
Bowen  as  affording  favorable  prospects. 

The  same  formations  that  produce  the  oil  in  the  Elk  Basin  and 
Big  Horn  Basin  of  Wyoming  are  found  here.  In  those  fields  the 
oil  comes  chiefly  from  the  Mowry  and  Frontier  formations,  and  at 
Basin,  Wyoming,  oil  is  obtained  from  the  Grey  bull  sand,  the  upper 
member  of  the  Cloverly.  Sections  indicate  that  the  sands  in  the 
Colorado  shale  in  the  Musselshell  Valley  occupy,  in  a  general  way, 
the  same  stratigraphic  position  as  the  productive  sands  in  the  Elk 
and  Big  Horn  basins. 

Sandstones  that  would  serve  as  suitable  reservoirs  for  the  accu- 
mulation of  oil  occur  at  several  horizons.  (1)  Near  the  top  of  the 
Colorado  shale  there  is  a  transition  zone  of  thin  sandstones  and 
sandy  shale  beds.  (2)  About  1,200  feet  below  the  top  of  the  Col- 
orado a  thick  porous  sandstone,  slightly  conglomeratic  at  the  top, 
is  well  developed  in  the  western  part  of  the  field  but  seems  to  be 
nearly  or  quite  absent  in  the  eastern  part.  This  sandstone  has 
approximately  the  same  stratigraphic  position  as  some  of  the  sand- 
stones in  the  Frontier  formation.  (3)  About  250  to  300  feet  lower 
in  the  section  is  another  sandstone  of  similar  character  but  much 
thinner  and  more  distinctly  conglomeratic.  (4)  Associated  with 
and  underlying  the  Mowry  shale  member,  in  the  eastern  part  of 

^OWEN,  C.  F. :  Anticlines  in  a  Part  of  the  Musselshell  Valley,  Montana. 
U.  S.  Geol.  Survey  Bull.  691,  pp.  185-209,  1918;  The  Stratigraphy  of  the 
Montana  Group.  U.  S.  Geol.  Survey  Prof.  Paper  90,  pp.  95-153,  1916. 


ROCKY  MOUNTAIN  FIELDS 


419 


GENERALIZED  SECTION  OF  GEOLOGIC  FORMATIONS  IN  A  PART  OF  THE  MUSSEL- 
SHELL  VALLEY,  MONTANA  (After  Bowen) 


System 

Group 

Average 

and 

and 

Thickness 

Characteristics 

Series 

Formation 

(Feet) 

Quaternary 

Alluvium. 

Unconsolidated  deposits  along  stream  courses. 

Tertiary 

Terrace  gravels 

0-80 

Terrace  gravel  of  well-rounded  pebbles. 

(Miocene(? 

TTnprmfnrmitv 

Tertiary(? 

Lance  forma 

Not    deter 

Yellowish-brown  sandstones  and  buff  to  gray  shales 

(Eocene  (?) 

tion. 

mined. 

with  a  thick,  massive  sandstone  at  base. 

Dark-gray  to  black  marine  clay  shale   containing 

B  e  a  r  p  a  w 

1  ,000  ± 

large  calcareous  concretions.    Heavy  band  of  sandy 

shale. 

concretions  near  base. 

An  upper  part,  chiefly  sandstone  and  shale,  forming 

ridges;  a  middle  part,  chiefly  light-buff  to  gray  or 

white  clay  shale  with  interbedded  sandstone;  a 

lower  part,  included  in  the  Judith  River  because 

d 

Judith  River 

550  * 

of  lithologic  similarity,  chiefly  sandstone  with  a 

formation  . 

thick  bed  of  massive  ledge-making  sandstone  at 

B 

the  base.     The  sandstones  become  andesitic  in 

= 

western  part  of  field. 

J3 

Claggett  for- 

350-490 

[n  eastern  part  of  field  a  dark-drab  shale.     It  be- 

S 

mation. 

comes  more  sandy  toward  the  west. 

Three  members.     Upper  member  moderately  thick 

sandstones  interbedded  with  shale;  middle  member 

shale  and  thin-bedded  sandstones;  lower  member 

Upper   Cre- 

Eagle sand- 

300 * 

(Virgelle  sandstone)   thick,  massive  white  sand- 

taceous. 

stone. 

stone.     In  western  part  of  field  lower  member  is 

thinly  bedded.     The  sandstones  become  andesitic 

toward  the  west. 

n  eastern  part  of  field  lower  400  to  500  feet  contains 

three    conglomeratic   sandstones    5    to    20    feet 

thick,  above  which  is  10  to  30  feet  of  sandy  shale 

which  contains  fish  remains.     This  represents  the 

Mowry  shale.     The  probable  representative  of  the 

Frontier  formation  is  a  zone  of  thin  shaly  sand- 

Colorado shale. 

2,200=t 

stones  about  30  feet   thick.     Farther  west,   the 

Mowry  shale  can  not  be  recognized.     The  lower 

700  or  800  feet  of  the  formation  consists  of  alternat- 

ing black  fissile  shale  and  thin  sandstones.     Above 

this  zone  is  the  Big  Elk  sandstone  member,  200  feet 

or  more  thick.     Remainder  of  formation  chiefly 
shale. 

Lower  Cre- 

^ootenai forma- 

250 + 

Vlainly  sandy  shale,  containing  concretionary  sand- 
stone in  the  upper  part.     At  the  top  is  about  50 

taceous. 

tion. 

feet  of  thin-bedded  sandstone  in  which  are  mark- 

ings resembling  worm  trails;  at  base  of  exposed  sec- 

tion is  a  coarse  sandstone. 

420 


GEOLOGY  OF  PETROLEUM 


the  field,  are  several  thin,  finely  conglomeratic  sandstones.  (5) 
At  the  top  of  the  Kootenai  there  is  40  to  50  feet  of  platy,  rather 
fine  grained  sandstone  in  approximately  the  same  position  as  the 
Greybull  sand  of  the  Big  Horn  Basin,  Wyoming.  (6)  Near  the  base 
of  the  Kootenai  there  is  another  coarse,  porous  sandstone  of  unde- 
termined thickness. 

North-central  Montana. — Interest  has  recently  been  attracted 
to  northern  Montana  by  a  large  gas  well  brought  in  near  Havre,1 
which  is  estimated  to  have  had  an  initial  yield  of  about  10,000,000 
cubic  feet,  but  proved  short-lived.  The  rocks  of  north-central 
Montana  are  sedimentary  beds  lying  almost  flat  that  have  been 


COLORADO  SHALE  S  ft) 

Betwee 
>tral  Fergus  Co.          and  C 
h  of  Lewistown 

•,  High 
real  F 

| 

1 

1 

wood  Mts.    Fr°m  log  °f  «ell  "ear  Sweet8r< 
'alls                  Kevin,  Toole  Co 

ogofv 
ssHil 

veil  in 
s  district 

c 

10'*  Gray  ss.. 

50'Gray  ss. 
70'x  Gray  ss. 

60'»  Conglom. 
and  gray  ss. 

cale 

£00  Ft. 

ipoo 

500 
0 

5'" 

10'- 

10'  Black  sandstone 

^^ 

itf  Dark-gray  ss. 
?o'lmpure  sandstone 
50'Gray  sandstone 

iScJ'Shale  with 
massive   sandstone 

— 

ez'Thinly  bedded  ss. 
/contains  fish  sca/es) 

8'  Coarse  grayish- 

— 

brown  sandstone 

^^ 

100*  "Rgsty  beds" 

25'" 

X 

Report 

ed  to  contain  sm 

a//  f/o 

tv  of  gas 

FIG.  173. — Section  showing  sandstones  in  lower  part  of  Colorado  shale,  north- 
central  Montana.  (After  Stebinger.) 

^TEBINGER,  EUGENE:  Possibilities  of  Oil  and  Gas  in  North-Central  Mon- 
tana. U.  S.  Geol.  Survey  Bull.  641,  pp.  49-91,  1917;  The  Montana  Group  of 
Northwestern  Montana.  U.  S.  Geol.  Survey  Prof.  Paper  90,  pp.  61-68,  1915. 

FISHER,  C.  A.:  Geology  of  the  Great  Falls  Coal  Field,  Montana.  U.  S. 
Geol.  Survey  Bull.  356,  1909;  Geology  and  Water  Resources  of  the  Great  Falls 
Region,  Montana.  U.  S.  Geol.  Survey  Water-Supply  Paper  221, 1909. 

PEPPERBERG,  L.  J.:  The  Milk  River  Coal  Field,  Montana.  U.  S.  Geol. 
Survey  Bull.  381,  pp.  82-107,  1910;  The  Southern  Extension  of  the  Milk  River 
Coal  Field,  Chouteau  County,  Montana.  U.  S.  Geol.  Survey  Bull.  471,  pp. 
359-383,  1912. 

Bo  WEN,  C.  F.:  The  Cleveland  Coal  Field,  Blaine  County,  Montana;  The 
Big  Sandy  Coal  Field,  Chouteau  County,  Montana.  U.  S.  Geol.  Survev 
Bull  541,  pp.  338-378,  1914. 


ROCKY  MOUNTAIN  FIELDS  421 

intruded  by  igneous  rocks  and  uplifted  in  isolated  mountain 
groups.  Faults  are  numerous.  In  the  plains  surrounding  the 
Bear  paw  Mountains  for  30  to  40  miles  on  all  sides  there  are  many 
folds  and  faults  in  the  Cretaceous  rocks.  These  are  irregular  in 
their  trend  and  distribution.  The  faulting  is  probably  related 
to  the  igneous  intrusions  in  the  Bear  paw  Mountains.  The  faults 
are  all  of  the  thrust  type,  older  formations  having  been  carried 
upward  beside  younger  rocks  that  lie  for  the  most  part  undis- 
turbed. Some  of  these  faults  are  about  12  miles  long. 

The  strong  flow  of  gas  encountered  at  Havre,  as  stated  by  Ste- 
binger,  comes  from  the  Eagle  sandstone.  The  gas  produced  at 
Medicine  Hat,  in  Alberta,  according  to  some  investigators,  is 
found  at  the  same  horizon.  Sections  of  the  Colorado  shale  are 
shown  on  Fig.  173. 

As  shown  by  the  tables  given  above  differences  between  the 
geologic  sections  of  the  eastern  and  western  parts  of  the  region 
occur  in  the  Montana  group  in  the  interval  between  the  Virgelle 
sandstone  and  the  Bearpaw  shale.  This  is  due  to  the  fact  that  the 
marine  invasion  during  which  the  Claggett  shale  was  deposited  in 
the  east  did  not  extend  westward  beyond  the  112th  meridian. 

Birch  Creek-Sun  River  Area. — The  Birch  Creek-Sun  River 
area1  in  northwestern  Montana,  lies  adjacent  to  the  front  range  of 
the  Rocky  Mountains,  between  Great  Falls  and  Kalispell.  The 
Cretaceous  formations  which  have  yielded  oil  and  gas  in  Wyom- 
ing, Colorado,  and  at  Medicine  Hat,  Alberta,  are  present  in 
this  area,  where  they  are  thrown  into  folds  along  axes  parallel  to 
the  front  range.  Some  wells  have  yielded  gas,  but  no  oil  field  has 
been  developed.  The  section  is  stated  below. 

Blackfeet  Reservation. — The  Colorado  shale  and  Kootenai 
formations  are  present  also  in  the  Blackfeet  Reservation,2  where 
locally  they  are  folded  and  faulted  (Fig.  174).  The  Colorado  and 
Bearpaw  shales  are  of  marine  origin  and  were  laid  down  in  separate 

^TEBINGER,  EUGENE  i  Oil  and  Gas  Geology  of  the  Birch  Creek-Sun  River 
Area,  Northwestern  Montana.  U.  S.  Geol.  Survey  Bull.  691,  pp.  149-184, 
1919. 

2STEBiNGER,  EUGENE:  Anticlines  in  the  Blackfeet  Indian  Reservation, 
Montana.  U.  S.  Geol.  Survey  Bull  641,  pp.  281-305,  1917;  Possibilities  of 
Oil  and  Gas  in  North-Central  Montana.  U.  S.  Geol.  Survey  Bull.  641, 
pp.  49-91,  1916;  Geology  and  Coal  Resources  of  Northern  Teton  County, 
Montana.  U.  S.  Geol.  Survey  Bull.  621,  pp.  117-156,  1916. 


422 


GEOLOGY  OF  PETROLEUM 


FORMATIONS  EXPOSED  IN  THE  PLAINS  OP  NORTH-CENTRAL  MONTANA  EAST 

OF  THE  112TH  MERIDIAN 

(After  Stebinger) 


System 

Series 

Group  and 
Formation 

Thickness 
(Feet) 

Character 

Quaternary  . 

Recent. 

Alluvium. 

Silt,  sand,  and  gravel  along  flood 
plains  of  larger  streams. 

Pleistocene. 

Glacial  drift. 

0-200 

Boulder  clay,  gravel,  and  lake  silt 
and  clay.  Contains  boulders 
and  cobbles  of  granite,  gneiss, 
quartzite,  etc.,  transported  from 
the  northeast. 

Tertiary. 

Eocene. 

Fort  Union  forma- 
tion. 

"700  + 

Clay  shale,  sandstone,  and  coal 
beds.  Present  only  in  small 
areas.  Poorly  exposed. 

Tertiary  (?). 

Eocene  (?). 

Lance  formation. 

700-800 

Alternating  gray  clay  shale  and 
sandstone  with  irregular  coal 
beds.  Present  in  relatively 
small  areas  only. 

Cretaceous. 

Upper    Cre- 
taceous. 

Q. 

1 

5 
a 

^0 

Bearpaw  shale. 

500-800 

Dark-gray  clay  shale  with  a  few 
limestone  concretions.  Contains 
many  marine  shells.  Forms  a 
subdued,  rounded  topography 
and  gumbo  soil. 

Judith  River  for- 
mation. 

450-550 

Light-gray  clay  and  clay  shale  with 
irregular  beds  of  gray  or  brown 
sandstone,  and  'coal  beds.  Con- 
tains many  oyster  and  other 
shells  besides  fossil  bones. 

Claggett  shale. 

350-500 

Like  the  Bearpaw  in  character  of 
rocks  and  fossils,  except  for  the 
occurrence  of  sandy  beds  near 
the  top. 

Eagle  sandstone 
with  Virgelle 
sand  stone 
member  at 
base. 

250-400 

Upper  part  gray  clay  shale  and 
sandstone  with  coaly  shale  and 
thin  coal.  Lower  part  white  to 
buff  thick-bedded,  massive  sand- 
stone, Virgelle  sandstone  mem- 
ber. Contains  gas  in  the  Havre 
district. 

Colorado  shale. 

1  ,500-1  ,700 

Bluish-gray  to  black  shale  with  a 
few  limestone  concretions.  Con- 
tains many  marine  shells.  In- 
cludes three  or  four  sandy  beds  5 
to  70  feet  thick  in  lower  800  feet. 
Probably  contains  gas  and  oil  in 
some  localities  of  favorable 
structure. 

Lower    Cre- 
taceous. 

Kootenai    forma- 
tion. 

400-600 

Red  clayey  shale  and  irregular 
gray  sandstone  with  a  few  thin 
beds  of  limestone.  Contains 
coal  near  the  base  and  fossil 
plant  remains  of  fresh-water 
origin.  Probably  contains  gas 
and  oil  in  some  localities  of 
favorable  structure. 

"Estimated. 


ROCKY  MOUNTAIN  FIELDS 


423 


FORMATIONS  EXPOSED  IN  THE  PLAINS  OF  NORTH-CENTRAL  MONTANA  WEST 
OF  THE  112TH  MERIDIAN 
(After  Stebinger) 


System 

Series 

Group  and 
Formation 

Thickness 
(Feet) 

Character 

Quaternary  . 

Recent. 

Alluvium. 

Silt,  sand  and  gravel  along  flood 
plains  of  larger  streams. 

Pleistocene. 

Glacial  drift. 

0-200 

Boulder  clay,  gravel,  and  lake  silt 
and  clay.  Contains  boulders 
and  cobbles  of  granite,  gneiss, 
quartzite,  etc.,  transported  from 
the  northeast. 

Cretaceous. 

Upper    Cre- 
taceous. 

Montana  group. 

Bearpaw  shale. 

450-550 

Dark-gray  clay  shale  with  a  few 
limestone  concretions.  Contains 
many  marine  shells.  Forms  a 
subdued,  rounded  topography. 

Two  Medicine 
formation. 

1,900-2,100 

Gray  to  greenish-gray  clay  and 
soft,  irregular  sandstone,  which 
is  most  abundant  in  the  lower 
250  feet.  In  places  thin  beds  of 
red  clay  and  nodular  limestone. 
Contains  an  abundant  reptilian 
fauna  of  Judith  River  types,  be- 
sides leaves  and  shells.  Contains 
coal  beds  near  the  base  and  at 
the  top. 

Virgelle  sand- 
stone. 

200-290 

Gray  to  buff  coarse-grained,  much 
cross-bedded  massive  sandstone, 
with  many  ferruginous  concre- 
tions in  upper  half.  In  lower 
half  slabby  gray  sandstone,  be- 
coming shaly  toward  the  base. 

Colorado  shale. 

1  ,600-1  ,750 

Bluish-gray  to  black  shale  with  a 
few  limestone  concretions.  Con- 
tains many  marine  shells.  In- 
cludes three  or  four  sandy  beds 
5  to  70  feet  thick  in  lower  800 
feet.  Probably  contains  gas  and 
oil  in  some  of  the  areas  of  favor- 
able structure. 

Lower    Cre- 
taceous. 

Kootenai   forma- 
tion. 

600-700 

Shale,  red  in  upper  part,  but  re- 
mainder grayish  to  black.  Con- 
tains irregular  sandy  beds  up  to 
100  feet  thick.  Fresh  water. 
Probably  contains  gas  and  oil  in 
some  of  the  areas  of  favorable 
structure. 

424 


GEOLOGY  OF  PETROLEUM 


FORMATIONS  EXPOSED  IN  THE  BIRCH  CREEK-SUN  RIVER  AREA,  MONTANA 

(After  Stebinger) 


System 

Series 

Group  and 
Formation 

Thickness 
(Feet) 

Character 

Quaternary  . 

Recent. 

Alluvium. 

Silt,  sand,  and  gravel,  chiefly  along 
stream  bottoms. 

Pleistocene. 

Glacial  drift. 

0-150 

Moulder  clay,  gravel,  and  sand. 
Contains  boulders  of  various 
rocks  derived  from  the  moun- 
tains. 

Tertiary. 
Tertiary  (?). 

Pleistocene 
and   late 
Tertiary. 

Terrace  gravels. 

5-50 

Limestone  gravels  on  terraces  and 
plains. 

Eocene  (?). 

St.  Mary  River  for- 
mation. 

650  + 

Clay,  clay  shale,  and  soft  sand- 
stone, gray  to  greenish  gray. 

Cretaceous. 

Upper   Cre- 
taceous. 

Montana  group. 

Horsethief  sand- 
stone. 

250-400 

Chiefly  massive  gray  to  buff  and 
greenish-gray  coarse-grained 
sandstone  with  slabby  sand- 
stone and  shale  in  lower  half. 
Contains  one  or  more  shell  beds. 

Bearpaw  shale. 

0-500 

Dark-gray  shale  with  a  few  thin 
beds  of  gray  sandstone.  Marine 
shells  of  Pierre  types.  Present 
only  in  northern  part  of  area. 
To  south  grades  into  brackish 
and  fresh  water  clays  and  sand- 
stones. 

Two  Medicine 
formation. 

1  ,800-2  ,200 

Gray,  greenish-gray,  and  red  clay 
and  clay  shale  with  subordinate 
irregular  sandstones,  mainly  in 
lower  half.  Bones  of  reptiles  of 
Judith  River  types  and  frag- 
ments of  wood  are  abundant. 
Thin  beds  of  coal  near  base. 

Virgelle  sand- 
stone. 

200-380 

Upper  part,  massive  coarse  gray 
sandstone,  much  cross-bedded, 
and  with  heavy,  irregular  beds 
of  magnetite  sandstone  at  top. 
Lower  part,  interbedded  sand- 
stone and  shale.  Contains  gas  at 
Medicine  Hat  and  elsewhere  in 
Alberta  and  at  Havre,  Montana. 

Colorado  shale  with 
Blackleaf   sandy 
member  at  base. 

1  ,800  + 

Upper  part,  dark  shale  with 
bituminous  shale  and  thin, 
maltha  -  bearing  limestones 
near  base.  Blackleaf  sandy 
member,  coarse  sandstones  lo- 
cally conglomeratic  in  beds  20 
to  75  feet  thick,  alternating  with 
dark  marine  shale;  thickness  610 
to  700  feet. 

Lower   Cre- 
taceous. 

Kootenai   forma- 
tion. 

890-920 

Red  and  green  shales  and  clay 
shale  with  many  beds  of  coarse 
gray  sandstones.  Contains  a 
few  fresh-water  shells. 

Jurassic. 

Upper  Juras- 
sic. 

Ellis  formation. 
-Unconformity  

Madison  and  later 
limestones. 

240-310 

Black  to  gray  calcareous  shale  with 
thin  limestone  and  sandstone. 
Many  fossil  shells.  Marine. 

Carbonifer- 
ous. 

Mississip- 
pian. 

1  ,200  + 

Massive  white  limestone,  cherty 
in  middle  and  lower  beds;  coral- 
line limestone  in  upper  beds. 

ROCKY  MOUNTAIN  FIELDS 


425 


FORMATIONS   OCCURRING   EAST   OF  THE    MOUNTAINS   ON   THE    BLACKFEET 

INDIAN  RESERVATION,  MONTANA 

(After  Stebinger) 


System 

Series 

Group  and 
Formation 

Thick- 
ness in 
Feet 

Character  of  the  Rocks 

Quaternary  . 

Recent. 

Alluvium. 

Deposits  of  small  extent  found  along 
flood  plains  of  the  larger  streams. 

Pleistocene. 

Glacial  drift. 

Boulder  clay,  gravel,  and  lake  silt 
and  clay.  Contains  boulders  and 
cobbles  of  granite,  gneiss,  quartz- 
ite,  etc.,  transported  from  other 
regions.  Deposits  are  of  several 
stages  not  distinguished  in  this 
report. 

Tertiary  (?). 

Eocene  (?). 

Willow   Creek   for- 
mation. 

720  + 

Variegated  clay  and  soft  sandstone, 
chiefly  maroon  to  chocolate-brown. 
Fragments  of  fossil  bones  common. 
Clay  in  places  contains  thin,  lentic- 
ular beds  of  limestone.  Forms  a 
red  soil.  Top  not  seen. 

St.  Mary  River  for- 
mation     (coal 
bearing). 

980 

Alternating  clay,  shale,  and  sand- 
stone much  cross-bedded  and 
ripple  marked.  Gray  to  greenish 
gray;  a  few  layers  are  red.  Con- 
tains thin  lenticular  limestones, 
fragments  of  dinosaur  bones,  and 
fossil  shells. 

Cretaceous. 

Upper   Cre- 
taceous. 

5- 
E 

M 

ti 
G 

r, 

3 

2 

Horsethief  sand- 
stone. 

225-375 

Gray  to  greenish-gray  sandstone. 
Thin  bedded  and  shaly  in  lower 
half.  In  upper  half  generally  mas- 
sive and  concretionary.  In  places 
near  the  top  contains  titaniferous 
magnetite.  Has  many  shell  beds, 
mainly  of  oysters. 

Bearpaw  shale. 

490 

Dark-gray  clay  shale  with  a  few 
limestone  concretions.  Contains 
abundant  marine  shells.  Forms 
subdued,  rounded  topography. 

Two  Medicine 
formation 
(coal  bearing). 

1,950 

Gray  to  greenish-gray  clay  and  soft 
sandstone,  most  abundant  in  the 
lower  250  feet.  In  places  beds  of 
red  clay  and  nodular  limestone. 
Contains  a  reptilian  fauna.lbesides 
leaves  and  shells.  Coal  beds  near 
base  and  at  top. 

Virgelle  sand- 
stone. 

220 

Gray  to  buff  coarse-grained  sand- 
stone, with  ferruginous  concre- 
tions in  upper  half.  In  lower  half 
slabby,  gray  sandstone,  shaly 
toward  the  base.  Contains  gas  in 
the  Havre  field  and  at  Medicine 
Hat. 

Colorado  shale. 

1  ,500  * 

Bluish-gray  shale  with  a  few  lime- 
stone concretions.  Contains  an 
abundance  of  marine  shells.  Forms 
a  subdued  and  rounded  topography. 
Complete  undisturbed  section  not 
present.  May  contain  oil  and  gas 
in  areas  of  favorable  structure. 

Lower   Cre- 
taceous. 

Kootenai    forma- 
tion. 

2,000± 

Gray  sandstone  and  shale,  alternat- 
ing with  maroon  clay  shale.  Some 
of  the  sandstone  massive.  Con- 
glomerate 6  to  50  feet  thick  near 
center.  Carries  a  few  leaves  and 
fresh-water  shells.  Complete  un- 
disturbed section  not  found.  May 
contain  oil  and  gas  in  areas  of 
favorable  structure. 

426 


GEOLOGY  OF  PETROLEUM 

epochs,  during  which  a  comparatively  shal- 
low sea  covered  the  entire  region.  The  re- 
^  maining  formations  are  mainly  of  conti- 
Is  nental  origin — that  is,  they  are  irregularly 
J  bedded  rocks  that  were  for  the  most  part 
*2  deposited  by  streams  and  winds  on  land 

5  areas  that  were  only  slightly  above  sea  level. 
The  most  promising  areas  for  prospecting 

g     are    those    containing    marine    formations 

-g     gently  folded  and  not  too  highly  faulted. 

o 

Bowdoin  Dome. — The  Bowdoin  dome1  is 

o  on  Milk  River,  in  northeastern  Montana,  on 

"I  the  Great  Northern  Railway,  between  Malta 

|  on  the  west  and  Hinsdale  on  the  east.  A  well 

P3  drilled  here  for  water  several  years   ago 

.1  yielded  a  small  flow  of  gas.  The  sedimen- 

£  tary  rocks  range  in  age  from  Cambrian  to 

•g  Recent,   but   only   the   Upper   Cretaceous 

3  Claggett  shale,  Judith  River  formation,  and 

g  Bearpaw  shale  and  some  of  the  more  recent 
surficial  deposits  are  exposed  in  the  immedi- 

'H  ate  vicinity  of  the  dome.  The  Claggett  shale 

6  crops  out  in  the  Little  Rocky  Mountains, 
«  about  50  miles  to  the  southwest.  The  sur- 
•|  face  of  the  Bowdoin  dome  is  covered  by  the 
"I  Claggett  shale,  below  which,  according  to 
jg  Collier,  are  four  sandstones  within  3,000  feet 
^  of  the  surface.  Of  these  four  the  Eagle  sand- 
.£  stone  yields  gas  at  Havre. 

Eastern  Montana. — Small  amounts  of  gas 

&  have  been  encountered  at  several  places  in 

.2  eastern  Montana  or  western  North  Dakota, 

jj>  most  of  them  in  wells  sunk  for  water.  In  the 

I.  southeastern  part  of  Dawson  County  the 

2  Glendive  anticline  is  well  defined.  It  extends 

o"  into  North  Dakota  and  is  one  of  the  most 
£ 

COLLIER,  A.  J. :  The  Bowdoin  Dome,  Montana, 
a  Possible  Reservoir  of  Oil  or  Gas.  U.  S.  Geol. 
Survey  Bull.  661,  pp.  133-209,  1917. 


ROCKY  MOUNTAIN  FIELDS 


427 


GENERAL  SECTION  OF  THE  ROCKS  OP  THE  BOWDOIN  DOME,  MONTANA 

(After  Collier) 


System 

Series 

Group 

Formation 

Thick- 
ness 
(Feet) 

Character 

Recent. 

Silts  in  the  flood  plains  of 
streams. 

Scattered  crystalline  boulders; 
glacial  moraines. 

Quaternary. 

Pleistocene. 

Silt,  sand,  and  gravel  deposited 
along  the  old  channels  of  the 
Missouri,  Musselshell,  and 
other  streams  before  the  end 
of  the  glacial  epoch. 

Gravel  interstratified  with  yel- 
lowish silt  at  an  altitude  of 
300  feet  above  Milk  River 
valley.  May  possibly  be 
late  Pliocene. 

Bearpaw  shale. 

800- 
1,000 

Dark-gray  shale;  forms  gumbo 
soil. 

Judith   River 
formation. 

400 

Light-gray  clay  and  irregular 
beds  of  gray  and  brown 
sandstone. 

Montana  . 

Claggett  shale. 

750 

Dark-gray  shale;  forms  gumbo 
soil.  About  500  feet  exposed 
in  Bowdoin  dome. 

Eagle  (?)  sand- 
stone. 

100  * 

l,ight-gray  sandstone;  forms  a 
low  ridge;  contains  limestone 
concretions  in  its  upper  part. 

taceoua. 

875 

Bluish-gray  to  black  shale;  con- 
tains limestone  concretions 
and  marine  fossils. 

60± 

Light-gray  sandstone,  capped 
by  a  thin  limestone  contain- 
ing numerous  gastropods. 

485  * 

Bluish-gray  to  black  shale. 

\lowry  shale. 

100  ± 

Platy  shale  or  sandstone,  which 
is  in  places  dark-colored  but 
weathers  white;  contains 
numerous  fish  scales;  yields 
traces  of  oil  by  distillation. 

Lower   Cre- 
taceous. 

Cootenai  (?) 
formation. 

825  ± 

Mainly  nhale  but  includes  some 
poorly  defined  sandstone.  In 
lower  part  red  and  purple 
shales  wei  e  noted.  A  bed  of 
fresh-water  sandstone  and 
caibonaceous  shale  with  frag- 
ments of  woody  stems  near 
the  base. 

Jurassic. 

Jpper  Juras- 

Ellis   forma- 

200  ± 

Massive  white  and  yellow  sand- 
stone. 

200  ± 

hale  containing  Belemnites. 

Carbonifer- 
ous. 

M  i  s  s  i  s  s  i  p- 
pian. 

Madison  lime- 
stone. 

Massive  limestone. 

428  GEOLOGY  OF  PETROLEUM 

prominent  structural  features  in  the  region.  It  exposes  a  belt  of 
Cretaceous  rocks  about  100  miles  long,  flanked  on  both  sides  by 
Tertiary  deposits.  On  this  anticline  gas  is  obtained,  probably 
from  sands  of  the  Judith  River  group  of  the  Montana.  It  is  used 
to  supply  Glendive  and  Baker.  Gas  is  found  in  the  Eagle  sands 
near  Hinsdale,  Valley  County.  Several  low  anticlines  near  Wolf 
Point  and  Poplar,  Valley  County,  are  reported.  These  are  prob- 
ably part  of  the  Glendive  system,  and  they  expose  near  their 
crests  the  upper  parts  of  the  Upper  Cretaceous, 

NORTH  DAKOTA 

At  Williston  and  Minot,  North  Dakota,  wells  have  been  drilled 
in  search  of  oil,  but  at  neither  place  have  commercial  accumula- 
tions been  found,  though  small  samples  resembling  gasoline  are 
said  to  have  been  obtained  from  the  Minot  well.  The  towns  of 
Westhope  and  Lansford,  in  Bottineau  County,  are  supplied  with 
natural  gas  from  shallow  wells  in  the  glacial  drift  above  the  Pierre 
shale.  At  Edgeley,  Lamoure  County,  artesian  wells  drilled  to  the 
Dakota  sandstone  yield  a  small  quantity  of  gas  which  is  separated 
from  the  water  by  mechanical  means  and  used  by  the  residents.1 

The  rocks  of  North  Dakota  in  general  lie  nearly  flat;  anticlines 
or  domes  are  not  easily  detected.  Underlying  the  area  the  shale 
and  fine-grained  sandstone  of  the  Fort  Union  (Eocene)  and  Lance 
(Eocene?)  formations  reach  a  depth  estimated  at  about  1,700  feet. 
The  Lance  carries  dinosaur  fossils  and  is  of  fresh-water  origin. 
Beneath  the  Lance  formation  is  the  Pierre,  composed  almost 
entirely  of  dark-gray  shale.  No  sandstone  layers  are  known  to  be 
present  in  the  upper  part  of  the  Pierre. 

The  Nesson  anticline,2  named  from  a  small  village  in  Williams 
County,  in  the  northwest  corner  of  North  Dakota,  is  about  30 
miles  east  of  Williston,  13  miles  southeast  of  Ray,  and  80  miles 
west  of  Minot.  It  was  discovered  in  1917  by  a  United  States 
Geological  Survey  party  which  mapped  outcrops  of  the  lignite 
beds  in  the  Ray  quadrangle. 

LEONARD,  A.  G. :  Natural  Gas  in  North  Dakota.  U.  S.  Geol.  Survey  Bull. 
431,  pp.  7-10,  1911. 

2CoLLiER,  A.  J. :  The  Nesson  Anticline,  Williams  County,  North  Dakota. 
U.  S.  Geol.  Survey  Bull  691,  pp.  211-217,  1919. 


ROCKY  MOUNTAIN  FIELDS 


429 


COLORADO 

General  Features. — The  production  of  oil  in  Colorado  has  never 
been  large  and  now  is  dwarfed  in  comparison  with  that  of  Wyom- 
ing. The  principal  producing  areas  are  the  Florence  and  Boulder 
fields,  in  both  of  which  the  oil  comes  from  the  Pierre  shale.  In  the 
San  Juan  field,  Utah,  oil  has  been  found  in  the  Goodridge  forma- 
tion (near  top  of  Pennsylvanian) .  In  the  De  Beque  field  oil  is  found 
probably  in  the  Mesaverde  or  at  the  base  of  the  Wasatch.  In  the 
Rangely  district,  Rio  Blanco  County,  some  oil  is  found  in  the 
Mancos  formation.  At  Urado,  near  Black  Dragon  station,  near 
the  western  boundary  of  Rio  Blanco  County,  a  little  oil  comes 
from  a  horizon  not  far  below  the  base  of  the  Green  River  oil  shales. 


PETROLEUM  MARKETED  IN  COLORADO)  1908-1917,  BY  DISTRICTS 


Boulder 

Florence 

Total 

Year 

Quantity 
(Barrels) 

Value 

Average 
Price  per 
Barrel 

Quantity 
(Barrels) 

Value 

Average 
Price  per 
Barrel 

Quantity 
(Barrels) 

Value 

Average 
Price  per 
Barrel 

1908 

84,174 

$124,794 

$1  482 

295,479 

$221,609 

$0  750 

379,653 

$346,403 

$0.913 

1909  

85,709 

129,812 

1.514 

225,062 

187,900 

.834 

"310,861 

318,162 

1.023 

1910 

42,186 

63,420 

1  503 

193,482 

174,332 

901 

&239,794 

243,402 

1.015 

1911  
1912 

37,973 
15,304 

50,393 
19,130 

1.327 
1  250 

187,341 
190,498 

175,763 
180,281 

.938 
946 

&226,926 
'206,052 

228,104 
199,661 

1.005 
.969 

1913  
1914 

11,796 
6,515 

15,366 
9,117 

1.303 
1  399 

176,693 
215,548 

159,103 
191,067 

.900 
886 

c  188,  799 
<*222,  773 

174,779 
200,894 

.926 
.902 

1915  
1916 

6,376 
5,749 

9,679 
9,902 

1.518 
1  722 

202,069 
191,486 

173,506 
207,237 

.859 
1.082 

"208,475 
197,235 

183,485 
217,139 

.880 
1.101 

1917  

5,847 

11,510 

1.969 

114,664 

115,150 

1.004 

"121,231 

128,100 

1.057 

"Includes  a  small  production  in  Garfield  County. 
^Includes  production  in  Garfield  and  Rio  Blanco  Counties. 
Includes  production  in  Rio  Blanco  County, 
''includes  production  in  Mesa  and  Rio  Blanco  Counties. 

Florence. — The  Florence  field,1  in  south-central  Colorado,  is  in 
a  synclinal  reentrant  of  the  Rocky  Mountain  front,  between  the 
fold  made  by  the  Front  range  on  the  northeast  and  the  Wet  Moun- 
tains on  the  southwest.  This  reentrant  is  commonly  called  Canon 
City  embayment.  The  rocks  are  Paleozoic  and  Mesozoic  sedi- 
ments. Solid  bitumen  is  found  in  the  Dakota  sandstone  near 
Canon  City,  and  about  7  miles  northeast  of  Canon  City  there  is  an 
oil  spring,  running  less  than  20  gallons  of  oil  a  day.  It  issues  from 
Pleistocene  gravel  but  probably  rises  from  the  Morrison  beds. 

WASHBURNE,  C.  W.  I  The  Florence  Oil  Field,  Colorado.  U.  S.  Geol.  Sur- 
vey Bull  381,  pp.  517-544,  1910. 


430 


GEOLOGY  OF  PETROLEUM 


Two  other  oil  springs  have  been  noted  in  Morrison  beds.     The 
producing  wells  are  in  the  Pierre  shale  (Upper  Cretaceous),  which 


EXPLANATION   ' 

La  ramie  ?,.etc,  ESSSSfDakota"    gggg§)  Ordovician. 
Pierre              u^_ j  Morrison  m-X-r'i  Granite 
Niobrara         ESSSTRed  Beds"  ESSE3  Igneous 
B_enton  mnn  Millsap     1 -"I  Faults 

OOOO  Oil  wells 

0  2 +  6  6 


loMiles 


FIG.  175.  —  Geologic  sketch  map  of  the  Canyon  City  embayment,  Colorado. 

Dor/on.) 


is  a  remarkably  uniform  rock.     Underground  it  is  firm  and  easily 
broken  along  the  bedding  planes. 

The  syncline  on  which  the  field  is  situated  (Fig.  175)  has  gen- 


ROCKY  MOUNTAIN  FIELDS  431 

erally  low  dips,  on  which  there  are  small  folds  passing  into  faults 
with  a  general  east- west  trend  and  a  throw  of  less  than  50  feet. 
These  folds  and  faults  probably,  indicate  the  fissures  below  them 
in  the  oil-bearing  zone.  The  oil  occurs  in  fissures  having  the  same 
direction  as  the  flexures,  and  the  presence  of  east-west  fissures  and 
flexures  at  the  surface  is  a  favorable  indication  of  the  productive 
character  of  the  locality.  The  Pierre,  which  crops  out  in  the 
region  of  the  wells,  is  productive  through  a  zone  2,500  feet  thick. 
It  carries  marine  fossils.  The  oil  is  rather  light  (30°Baume),  has 
a  paraffin  base,  and  is  free  from  sulphur.  It  is  associated  with  gas, 
and  the  deep  wells  encounter  salt  Water.  As  a  rule,  however, 
water  does  not  follow  the  oil  when  the  well  is  pumped  dry. 

Boulder. — The  Boulder  oil  district1  lies  a  few  miles  north  of 
Boulder,  east  of  the  Front  range.  The  rocks  dip  eastward,  away 
from  the  mountains.  Locally  small  foothill  folds  are  developed. 
The  section  includes  the  following  strata. 

Quaternary Alluvium  and  terrace  gravels 

Laramie 
Fox  Hills 


Cretaceous. 


Pierre 


Niobrara 
Benton 

v  Dakota 
Jurassic Morrison 

I  Lykins 
Triassic  (?) I  Lyons 

[Fountain 

Algonkian Quartzite  of  South  Boulder  Canyon 

Archean .  .  .  Granites,  etc. 

The  Pierre  is  more  than  5,000  feet  thick  and  is  mainly  shale  with 
a  little  limestone  and  sandstone.  It  contains  also  the  Hygiene 
sandstone  member  and  other  lower  sandstones.  Near  Boulder 
the  Hygiene  sandstone  is  within  less  than  1,000  feet  of  the  base  of 
the  Pierre  and  is  itself  a  very  thin  stratum.  It  thickens  greatly 
toward  the  north,  as  do  the  shales  which  lie  below  it.  Oil  springs 
are  found  about  10  miles  from  Boulder,  and  one  some  17  miles 
north  is  noteworthy.  Oil  development  appears  not  to  have  been 
suggested  by  the  springs,  however,  but  the  bituminous  odor  of  the 
Benton  and  Niobrara  shales  led  to  the  exploration.  Later,  in 

'FENNEMAN,  N  M.:  Geology  of  the  Boulder  District,  Colorado.  U.  S. 
Geol.  Survey  Bull  265,  1905. 


432  GEOLOGY  OF  PETROLEUM 

prospecting  for  coal,  oil  was  found  in  the  Pierre,  much  higher  than 
these  formations.  The  beds  from  which  the  oil  is  obtained  are 
sands  or  sandstones  in  the  Pierre.  Such  beds  may  be  encountered 
at  any  depth,  but  there  is  no  depth  at  which  they  are  certain  to  be 
found.  Some  of  the  wells  are  dry;  others  yield  salt  water.  In  the 
part  of  the  field  near  Boulder  that  had  been  developed  when  the 
field  was  described  by  Fenneman  the  oil  accumulations  appear  to 
have  no  very  definite  relation  to  the  structure.  Later  an  anticline 
in  the  area  to  the  north,  shown  in  Fenneman's  report  by  the  posi- 
tion of  the  Hygiene  sandstone  member  in  the  Pierre,  was  drilled. 
The  first  well,  a  gusher,  was  brought  in  on  the  south  end  of  this 
anticline.  It  had  an  initial  flow  of  250  barrels  a  day.  Eight  other 
wells  drilled,  pumped  from  5  to  170  barrels  a  day,  two  encountered 
traces  of  oil,  and  two  were  dry.  All  the  productive  wells  are  on 
the  anticline.  They  derive  their  oil  from  a  sandstone  in  the  Pierre 
shale,  2,000  to  2,500  feet  deep.  The  wells  sunk  near  the  crest  of 
the  anticline  produce  gas  and  a  light  oil  of  about  42°  Baume.  The 
wells  farther  down  the  limbs  of  the  anticline  produce  heavier  oil 
(40°  Baume),  mixed  with  water.1 

DeBeque. — The  DeBeque  oil  field2  is  on  the  Grand  River  in 
Mesa  County.  The  country  is  a  high  plateau  deeply  dissected. 
The  rocks  are  nearly  flat-lying,  and  the  formations  exposed  are 
the  Wasatch  and  Green  River.  Below  the  Wasatch  is  the  Mesa- 
verde  formation,  and  below  that  the  Mancos  shale  is  probably 
present.  The  section  is  stated  on  page  433. 

Structurally  the  region  is  a  saucer-like  basin  that  extends  from 
the  Uncompahgre  Plateau  on  the  southwest  to  the  Grand  Hogback 
on  the  northeast.  In  the  part  of  the  region  near  De  Beque  the 
rocks  generally  dip  northeast  or  lie  horizontal.  Due  west  of  De 
Beque,  however,  there  is  an  anticline  which  extends  westward  for 
about  8  miles  or  more.  South  of  the  axis  the  rocks  dip  2°-3°  S.; 
north  of  it  they  dip  3°-5°  N.  Oil  is  encountered  in  wells  on  the 
anticline  not  far  from  its  crest.  It  is  a  light-gravity  oil  (37C 
Baume)  with  a  paraffin  base,  free  from  asphalt. 

Oil  was  discovered  in  the  area  in  1902,  and  in  the  next  two  years 
ten  wells  were  drilled.  The  first  well  was  614  feet  deep.  Most 

^ASHBURNE,  C.  W.i  Development  in  the  Boulder  Oil  Field,  Colorado. 
U.  S.  Geol.  Survey  Bull  381;  pp.  514-516,  1910. 

2WooDRUFF,  E.  G. :  Geology  and  Petroleum  Resources  of  the  DeBeque  Oil  i 
Field,  Colorado.  U.  S.  Geol.  Survey  Bull  531,  pp.  54-68,  1913, 


ROCKY  MOUNTAIN  FIELDS 


433 


STRATIGRAPHIC   RELATIONS   OF  FORMATIONS  IN  THE   DE   BEQUE   REGION, 

COLORADO 
(After  Woodruff) 


System 

Series 

Formation 

Character 

Quaternary. 

Alluvium  in  valleys  and  gravel 
on  terraces,  variable  thick- 
ness. 

Tertiary. 

Eocene. 

Green  River  forma- 
tion. 

Shale  and  sandstone,  locally  cal- 
careous. The  shale  is  sandy, 
fine  grained,  and  evenly 
bedded;  faded  olive-green  in 
color.  The  sandstone  is  thin 
bedded  and  fine  grained.  . 

Wasatch  formation. 

Shale  and  sandstone,  irregularly 
bedded.  The  shale  is  varie- 
gated, shades  of  gray  and  pink 
predominating.  The  sand- 
stone is  coarse  grained  and 
variegated. 

Cretaceous. 

Upper  Cre- 
taceous. 

Mesaverde    forma- 
tion. 

Sandstone,  thick  bedded,  and 
sandy  shale.  Not  exposed  in 
this  region. 

of  the  wells  found  small  quantities  of  oil  and  gas,  but  no  clearly 
defined  oil  sand  was  encountered.  Woodruff  believes  that  the  oil 
and  gas  are  in  the  upper  part  of  the  Mesaverde  formation,  or  pos- 
sibly in  the  lower  Wasatch.  He  states  that  the  Mancos  shale, 
which  underlies  the  Mesaverde,  is  probably  the  original  source  of 
the  oil  rather  than  the  Green  River,  which  is  high  above  the  oil- 
bearing  strata. 

Rangely. — The  Rangely  district  is  in  Raven  Park,  Rio  Blanco 
County,  about  33  miles  northeast  of  Dragon,  Utah.1  Attention 
was  directed  to  this  field  by  the  discovery  of  an  oil  seep.  There 
are  about  20  wells  each  capable  of  producing  2  or  3  barrels  of  oil  a 
day.  Most  of  the  wells  are  400  to  600  feet  deep;  one  is  said  to  be 

JGALE,  H.  S.:  Geology  of  the  Rangely  Oil  District,  Rio  Blanco  County, 
r<>lor:ul<>.  V.  S.  Geol.  Survey  Bull.  350,  1908. 


434  GEOLOGY  OF  PETROLEUM 

over  3,000  feet  deep.  The  oil  is  a  high-grade  yellow  oil,  with  a 
gravity  of  44°  Baume,  and  according  to  report  is  burned  directly 
in  an  engine.  The  district  is  structurally  a  dome  or  quaquaversal 
which  exposes  the  Mancos  shale  and  is  superimposed  on  the  great 
structural  basin  that  lies  south  of  the  Uinta  Mountains.  The  oil 
is  found  in  thin  sand  lenses  in  the  Mancos  formation.  Both  the 
sands  and  shales  are  said  to  be  dry;  no  adequate  oil  sand  has  yet 
been  encountered.  The  Dakota  sandstone,  which  lies  3,500  or 
4,000  feet  below  the  surface,  has  not  been  tested.  In  general  it  is 
not  petroliferous  in  this  region. 

White  River.— The  White  River  field  is  on  Blacks  Gulch,  40 
miles  east  of  Rangely  and  20  miles  west  of  Meeker.  It  is  on  the 
crest  of  a  minor  anticline  that  lies  across  the  White  River  Valley.1 

The  dips  are  low,  being  about  3°  toward  the  east,  about  10° 
south  of  the  river,  and  about  5°  toward  the  west.  A  well  was  put 
down  400  feet  where  a  cowboy  had  discovered  a  flow  of  gas  by 
lighting  a  match.  Another  well  sunk  538  feet  struck  gas  under 
sufficient  pressure  to  destroy  the  derrick.  The  gas  burned  six 
months  and  then  ceased  to  issue.  No  oil  was  found.  The  strata 
are  Wasatch  at  the  surface,  flanked  by  Green  River  escarpments. 

Urado. — About  8  miles  south  of  Dragon  station,  Utah,  at  Urado, 
Rio  Blanco  County,  on  the  Uintah  Railway,  1J^  miles  east  of  the 
Colorado-Utah  line,  the  Urado  Co.  operates  an  oil  well  and  a  small 
refinery.  It  produces  lubricating  oils  of  high  quality  which  are 
sold  in  the  Uinta  Valley  region.  The  plant  is  said  to  be  capable 
of  producing  between  5  and  10  barrels  a  day.  A  well  505  feet 
deep  is  sunk  in  beds  that  lie  at  a  horizon  below  the  oil  shales  of  the 
Green  River  formation,  possibly  in  the  upper  beds  of  the  Wasatch. 
Drilling  was  suggested  by  the  presence  of  an  oil  spring.  The  beds 
are  practically  flat  or  dip  2°-3°  NW.  Oil  is  present  in  three  sands 
penetrated.  A  tunnel  375  feet  long  is  run  in  on  the  upper  sand  the 
entire  distance.  This  tunnel  was  bulkheaded  a  short  distance  in, 
and  the  structure  beyond  the  bulkhead  is  concealed.  Mr.  J.  T. 
Pope,  manager,  says  that  the  oil  sand  forms  a  shallow  syncline. 
There  is  little  or  no  gas  pressure,  and  no  gas  was  encountered  in 
driving  the  tunnel.  The  oil  sand  and  the  oil  lie  in  shallow  sags 
which  are  4  or  5  feet  deep.  The  oil  comes  into  the  sags  from  the 
southeast  and  issues  at  the  portal  of  the  tunnel. 
,  H.  S.:  Op.  ctt.,  p.  48, 


ROCKY  MOUNTAIN  FIELDS  435 

UTAH 

Green  River  District. — In  the  Green  River  district  of  Utah,  near 
the  town  of  Green  River,  on  the  Denver  &  Rio  Grande  Railroad, 
sandstones  saturated  with  petroleum  crop  out,  and  small  amounts 
of  oil  have  been  found  in  several  wells.  Oil  seeps  on  the  surface 
are  fairly  common.  The  geology  has  been  described  by  Lupton,1 
who  visited  the  field  in  1912.  The  rocks  exposed  are  of  Cretaceous 
and  Jurassic  age. 

The  oil  and  gas  are  in  the  McElmo  formation.  Of  wells  drilled 
prior  to  1912,  three  were  dry,  four  showed  gas,  and  three  showed 
traces  of  oil.  Gas  is  associated  wjth  salt  water  in  a  well  1,980 
feet  deep.  The  wells  passed  through  the  McElmo  formation  and 
penetrated  the  upper  part  of  the  La  Plata.  The  McElmo  con- 
tains no  persistent  oil  sand,  although  it  may  include  numerous 
small  lenses  of  petroliferous  sandstone. 

Structurally  the  region  is  a  monocline  dipping  northeast,  on. 
which  there  is  a  shallow  anticline  broken  by  faults.  The  dips  are 
low.  According  to  Lupton  there  are  no  good-sized  domes  or 
persistent  petroliferous  beds  in  the  McElmo  in  this  region. 

Hanksville. — Near  Hanks ville,  45  or  50  miles  southwest  of  Green 
River,  two  wells  were  being  drilled  in  1912.  Lupton,2  who  made 
a  reconnaissance  of  this  district,  states  that  the  structure  appears 
to  be  favorable  to  oil  accumulation,  providing  the  rocks  contain  a 
sand  and  oil.  A  broad,  low,  flat  east-west  anticline  connects  the 
San  Rafael  Swell  on  the  west  with  another  anticline  reported  to  be 
near  the  junction  of  the  Grand  and  Green  rivers. 

Salt  Lake  Basin.— Gas  has  been  found  at  several  places  in  the 
lake  deposits  of  Salt  Lake  basin  by  drilling  near  small  gas  seeps.3 
Several  wells  about  12  miles  north  of  Salt  Lake  City  supplied  gas 
for  domestic  use  for  a  time,  but  these  are  now  abandoned.  At 
Farmington  gas  was  found  under  heavy  pressure  at  several  hori- 
zons in  the  unconsolidated  material,  but  no  oil  was  discovered, 
although  in  a  well  2,000  feet  deep  some  oil  was  found  at  Fillmore, 
Utah,  south  of  Salt  Lake. 

LUPTON,  C.  T.:  Oil  and  Gas  Near  Green  River,  Grand  County,  Utah. 
U.  S.  Geol.  Survey  Butt.  541,  pp.  115-133,  1914. 

LUPTON,  C.  T. :  Op.  tit.,  pp.  120,  133. 

RICHARDSON,  G.  B. :  Natural  Gas  Near  Salt  Lake  City,  Utah.  U.  S.  Geol. 
Survey  Bull.  260,  pp.  480-483,  1905, 


43(5 


GEOLOGY  OF  PETROLEUM 


GENERAL  SECTION  OF  ROCKS  OUTCROPPING  IN  THE  GREEN  RIVER  FIELD,  UTAH 

(After  Lupton) 


Sys- 
tern 

For- 
ma- 
tion 

Member 

Character  of  Strata 

Thickness 
(Feet) 

Economic  Value 

Yellow  to  bluish  drab  sandy 
shale;  the  upper  part  is  very 
sandy  and  contains  beds  and 
lenses  of  sandstone;  the  middle 
and  lower  parts  are  mainly 
shale. 

About  2  ,500 
(after 
Richardson) 

!retaceous. 

Mancos  sh 

Perron  sand- 
stone mem- 
ber. 

This  sandstone  contains  in  places 
concretions  which  are  fossilif- 
erous.  It  forms  a  hogback 
through  the  field. 

50-100 

Possibly  this  sand- 
stone is  a  reservoir 
for  the  gas  that  has 
been  obtained  in 
some  of  the  wells. 

w 

Bluish  drab  sandy  shale;  sandy 
material  is  most  plentiful  near 
the  base  and  top  of  this  part  of 
the  formation. 

About  400. 

Dakota 
sandstone. 

Yellowish-gray  sandstone  with 
thin  beds  of  shale  alternating. 
Sandstones,  coarse,  soft,  and 
in  places  very  conglomeratic. 

0-40 

Contains  a  little  coal 
in  places,  but  none 
was  observed  in 
this  field. 

0 

1 

Gray  conglomerate,  variegated 
sandy  shale,  and  clay,  and  a 
few  feet  of  limestone  about 
175  feet  from  the  top. 

325-350 

A  few  lenses  of  sand- 
stone  contain 
pockets  of  gas. 
Other  lenses  are 
partly  saturated 
with  petroleum. 

3 

"-S 

cElmo  formal 

Salt  Wash 
sandstone 
member. 

3ray  conglomeratic  sandstone 
which  outcrops  in  cliffs.  The 
sandstone  in  places  is  lentic- 
ular, soft,  and  friable. 

150-175 

Water-bearing  in 
places.  Probably 
contains  a  little  gas 
and  a  trace  of  oil. 

5 

Red  sandstone,  thin-bedded 
above  and  massive  below. 

About  700. 

Gypsum  and  manga- 
nese in  the  upper 
part. 

Jurassic. 

II 

Coarse  gray  sandstone  very 
much  cross-bedded 

Estimated 
700. 

Water-bearing  in 
many  places. 

ROCKY  MOUNTAIN  FIELDS 


437 


Asphalt  is  found  near  the  Rozel  Hills,  on  the  north  shore  of  Salt 
Lake.1  The  occurrence  appears  to  be  restricted  to  the  shallow 
littoral  portion  of  the  lake,  one-fourth  to  one  mile  out  from  the 
present  shore  line,  immediately  southeast  of  the  Rozel  Hills.  The 
asphalt  exudes  through  the  unconsolidated  material  on  the  bottom 
of  the  lake  and  bubbles  up  into  the  water  in  the  form  of  hollow 
spherical  or  tubular  masses  1  to  2  inches  long  and  threads  and 
hairs  6  to  18  inches  long.  These  small  masses  spot  the  bottom  m 
great  numbers  throughout  this  area.  At  certain  points  the  emis- 
sions are  concentrated  into  considerable  seeps  or  "pitch  springs," 
1  to  2  feet  in  diameter.  The  source  of  these  seeps  appears  to  those 

SECTION  OF  STRATA  EXPOSED  IN  THE  SAN  JUAN  OIL  FIELD,  UTAH 
(After  Woodruff) 


System 

Formation 

Member 

Thick- 
ness 
(Feet) 

Description 

Jurassic. 

La   Plata  sand- 
stone. 

«500  = 

Massive,  tan  sandstone. 

Triassic. 
Unconformity?- 
Permian? 

Dolores  shale. 

1,330 

Very  sandy,  variegated 
shale.  This  formation 
contains  saurian  re- 
mains. 

Moencopie  forma- 
tion. 

Oljato 
sand- 
stone. 

20-380 

Massive,  tan  sandstone. 

1,260 

Red,  sandy  shale  and 
massive,  tan  sandstone 
beds. 

Pennsylvania!! 

Goodridge  forma- 
tion. 

1,542 

Massive-bedded,  crystal- 
line limestone,  soft, 
sandy  shale  and  sand- 
stone. Oil  near  top. 

"Only  lower  part  exposed. 

'BouTWELL,  J.  M.:  Oil  and  Asphalt  Prospects  in  Salt  Lake  Basin,  Utah. 
U.  S.  Geol.  Survey  Bull.  260,  p.  474,  1905. 


438 


GEOLOGY  OF  PETROLEUM 


if 


V 


Ill 


t 


who  have  prospected  this  ground  to  be 
a  bed  of  asphalt  2  or  3  feet  thick,  which 
was  encountered  80  feet  below  the 
present  lake  bed,  and  an  underlying 
series  of  asphaltic  beds  3  to  5  feet  thick, 
which  alternate  with  beds  of  clay  to  a 
depth  of  at  least  140  feet.  In  the  vicin- 
ity of  these  seeps  the  asphaltic  matter 
cements  the  calcareous  oolitic  deposits 
of  the  lake  bottom  into  a  bituminous 
limestone.  This  forms  numerous  low 
islets,  1  to  50  feet  in  diameter,  which 
are  distributed  in  rough  alinement. 
This  alinement  and  the  presence  of 
brecciated  zones  in  the  limestone  on 
the  mainland  suggest  the  possibility 
that  the  seeps  may  occur  along  zones 
of  fracture.  These  zones  may  have 
served  merely  to  open  exits  for  the 
fluid  asphalt  in  unconsolidated  lake 
beds,  or  they  may  have  also  delivered 
it  from  deeper  reservoirs  in  underlying 
bedrock  to  its  present  position. 

San  Juan  Field. — The  San  Juan  oil 
field1  is  in  southeastern  Utah,  about  20 
miles  west  of  Bluff,  where  several  oil 
seeps  occur  along  the  San  Juan  River. 
The  strata  of  this  region  are  indicated 
on  page  437. 

The  rocks  are  thrown  into  gentle 
folds,  whose  axes  trend  nearly  north. 
The  principal  structural  feature  is  a 
broad,  gentle  syncline,  flanked  by  anti- 
clines on  either  side.  There  are  several 
oil  sands,  all  near  the  top  of  the  Good- 

WOODRUFF,  E.  G.:  Geology  of  the  San 
Juan  Oil  Field,  Utah.  U.  S.  Geol.  Survey 
Bull  471,  p.  76,  1912. 

GREGORY,  H.  E. :  The  San  Juan  Oil  Field. 
U.  S.  Geol.  Survey  Bull  431,  pp.  11-25,  1911. 


ROCKY  MOUNTAIN  FIELDS  439 

ridge  formation,  whore  they  are  interbedded  with  shale.  Where 
not  exposed  the  Goodridge  is  overlain  by  the  lower  shales  of  the 
Moencopie.  All  the  oil  found  is  in  the  broad  syncline  (Fig.  176). 
There  is  very  little  water  in  the  oil-bearing  sands,  and  the  gas 
pressure  is  not  high.  The  oils  are  light  (37°  Baume)  and  carry 
high  percentages  of  gasoline  and  burning  oil,  with  considerable 
paraffin  wax.  Numerous  wells  have  encountered  oil,  and  one  well 
drilled  in  1908  sprayed  oil  70  feet  above  the  derrick  floor.  The 
pressure  in  general  is  low,  however,  and  the  sands  are  generally 
dry.  Developments  thus  far  are  not  particularly  promising. 

Virgin  City. — Virgin  City  is  on  Virgin  River,  in  the  southwest 
corner  of  Utah,1  about  90  miles  by  road  from  Lund,  the  nearest 
railroad  station,  which  is  on  the  Los  Angeles  &  Salt  Lake  Railroad. 
This  portion  of  the  Plateau  Province  is  underlain  by  almost  flat- 
lying  strata  which  range  in  age  from  Carboniferous  to  Eocene. 

Carboniferous  limestone  crops  out  a  few  miles  west  of  Virgin 
City,  and  the  town  is  immediately  underlain  by  the  Permian  (?) 
Red  Beds.  An  oil  seep  led  to  drilling  a  well  in  1907.  The  first 
well  struck  oil.  Six  wells  drilled  afterward  did  not  find  oil  in 

appreciable  amounts. 

NEW  MEXICO 

In  Eddy  and  Chaves  Counties,  New  Mexico,  in  the  Pecos  River 
basin,  petroleum  has  been  discovered  in  about  twenty  deep  wells 
drilled  for  artesian  water.  In  most  of  these  wells  only  conspicuous 
showings  of  oil  are  present.  In  one  a  considerable  flow  of  gas  was 
encountered.  Two  wells  have  produced  oil  in  small  quantities. 

The  country  is  a  broad,  nearly  level  valley  irrigated  by  artesian 
water,  of  which  there  are  good  flows  at  Artesia,  Dayton,  and  Lake- 
wood.  In  this  area  hundreds  of  wells  have  been  drilled,  ranging 
in  depth  from  300  feet  to  more  than  1,100  feet.  In  most  of  them 
water  rises  to  points  near  the  surface  or  flows  out  under  pressure. 

In  1910  gas  was  struck  in  a  well  896  feet  deep,  drilled  for  water 
about  l]/2  miles  southeast  of  Dayton.  The  flow  is  said  to  have 
burst  a  300-pound  gage  when  gas  was  first  encountered.  This 
well  is  now  fitted  with  a  gas  trap,  and  when  the  valve  is  opened  a 
strong  jet  of  inflammable  gas  issues. 

The  Williams  or  Belt  well,  2l/%  miles  east  of  Dayton,  is  about 
1,000  feet  deep.  Oil  and  gas  flow  out  with  the  water.  The  oil  is 

RICHARDSON,  G.  B.:  Petroleum  in  Southern  Utah.  U.  S.  Geol.  Survey 
Bull.  340,  pp.  343-347,  1908. 


440  GEOLOGY  OF  PETROLEUM 

allowed  to  settle  from  the  water  in  a  tank,  where  about  half  a 
barrel  a  day  is  recovered.  The  largest  well  in  this  region  is  the 
Brown  well,  about  2  miles  northeast  of  Dayton.  It  was  sunk  in 
1909  and  was  then  950  feet  deep.  Water  was  encountered  at  a 
depth  of  about  660  feet  and  oil  at  about  920  feet.  The  water  was 
partly  cased  off,  and  the  well  is  said  to  have  yielded  about  10 
barrels  of  oil  a  day. 

The  oil  of  this  region  is  a  heavy  black  fuel  oil  of  about  25° 
Baume.  It  has  an  asphalt  base  and  is  high  in  sulphur.  According 
to  analyses  made  by  David  T.  Day,  it  contains  no  gasoline  and 
carries  about  29  to  33  per  cent  of  kerosene.  Sulphur  gases  issue 
with  the  oil  and  from  some  of  the  water  wells  that  produce  little 
or  no  oil.  The  oil  from  the  Brown  well  carries  2.3  per  cent  of 
sulphur.  The  water  carries  sulphates  but  is  essentially  free  from 
sodium  chloride. 

The  rocks1  are  all  of  sedimentary  origin  and  dip  eastward  from 
the  Guadalupe  Mountains  to  the  Pecos  River.  Near  the  moun- 
tains the  rocks  dip  steeply;  in  the  valley  the  dips  are  lower.  In 
the  mountains  there  is  exposed  a  series  of  Pennsylvanian  lime- 
stones, estimated  to  be  about  10,000  feet  thick.  In  the  Pecos 
Valley  these  beds  are  covered  by  a  series  of  shales,  limestones,  and 
sandstones  with  gypsiferous  beds  containing  native  sulphur  which 
belong  to  the  Red  Beds,  of  Permian  age.  This  series  is  1,600  feet 
thick.  Farther  east  the  Permian  is  covered  by  Triassic  and  Ter- 
tiary rocks,  but  these  are  probably  absent  in  the  oil  district. 
Quaternary  gravels,  sands,  and  clays  cover  the  older  rocks  in  the 
Pecos  Valley.  Locally  this  unconsolidated  material  is  hundreds 
of  feet  thick,  effectively  covering  the  bedrock  in  the  valley  region. 

In  the  Pecos  Valley  fractured  limestones  are  overlain  by  shales. 
Water  enters  the  fractured  limestone  in  the  higher  country,  where 
precipitation  is  greater,  and  flows  eastward  underground.  Its 
escape  is  prevented  by  the  overlying  impervious  shales  and 
' 'gumbo."  The  limestone  is  very  permeable  locally,  owing  to 
fractures.  Near  Artesia  many  wells  flow  1,000  gallons  a  minute 
or  more.  At  places  the  limestone  is  probably  impermeable.  In 

WISHER,  C.  A.:  Preliminary  Report  on  the  Geology  and  Underground 
Waters  of  the  Roswell  Artesian  Area,  New  Mexico.  U.  S.  Geol.  Survey 
Water-Supply  Paper  158,  1904. 

RICHARDSON,  G.  B. :  Petroleum  Near  Dayton,  New  Mexico.  U.  S.  Geol. 
Survey  Bull.  541,  pp.  135-140,  1914. 


ROCKY  MOUNTAIN  FIELDS  441 

the  area  north  of  Artesia,  in  Cottonwood  Draw,  several  wells  have 
encountered  the  limestone  without  finding  a  water  supply. 

In  this  great  eastward-dipping  series  of  rocks  there  are  probably 
small  domes  superimposed  on  the  monocline.  One  such  dome  is 
said  to  be  present  near  Dayton. 

IDAHO  AND  OREGON 

Near  Payette,  Idaho,  and  Vale,  southeastern  Oregon,1  gas  and 
some  oil  are  found,  and  hot  springs  carry  inflammable  gas.  The 
rocks  of  the  area  are  of  fresh-water  origin  and  are  mainly  lake  beds, 
consisting  of  clays  and  sands  and  river  gravel  with  some  intrusive 
basalt  and  rhyolite.  The  sedimentary  rocks,  which  include  the 
Payette  formation  (Eocene  or  Oligocene)  and  the  Idaho  formation 
(Pliocene)  are  thrown  into  gentle  folds,  the  dips  being  as  a  rule 
less  than  7°.  There  is  very  little  faulting.  Traces  of  oil  and  gas 
seeps  are  found  at  many  places  in  southeastern  Oregon  and  on  the 
Snake  River  plains  of  Idaho,  and  small  mud  volcanoes  have  formed 
where  gas  seeps  issue.  About  10  miles  southwest  of  Vale  a  hard 
band  of  petroliferous  sandstone  runs  along  a  low  cliff.  It  has  a 
strong  odor  of  petroleum,  especially  near  some  faults  that  cut 
across  the  cliff.  A  similar  sandstone  is  found  about  3  miles  south- 
east of  this  point,  and  oil  is  present  at  several  other  places.  Sev- 
eral wells  have  been  put  down  in  this  region,  and  one  of  them  is 
3,650  feet  deep.  Gas  under  heavy  pressure  was  encountered  in 
several  wells  at  moderate  depth.  One  well  encountered  rock  salt ; 
another  salty  water.  Some  of  the  wells  are  said  to  encounter 
sulphur-bearing  rock.  No  oil  had  been  found  in  marketable  quan- 
tity. Washburne  considers  as  possible  the  hypothesis  that  the 
gas  and  oil  have  an  abyssal  or  solfataric  source. 

^VASHBURNE,  C.  W. :  Gas  and  Oil  Prospects  Near  Vale,  Oregon,  and  Pay- 
ette, Idaho.  U.  S.  Geol.  Survey  Bull,  431,  pp,  26-57,  1910. 


CHAPTER  XXI 

PACIFIC  COAST  FIELDS 
CALIFORNIA 

General  Features. — Petroleum  is  found  in  California  (Fig.  177) 
in  a  belt  about  225  miles  long  extending  from  the  Coalinga  district, 
in  Fresno  County,  at  the  north,  to  the  Puenta  Hills  district,  in 
Orange  County,  at  the  south.  The  fields  in  this  belt,  which  are 


0     10   ,20  43  60  80 


FIG.  177.— Map  of  part  of  California,  showing  oil  districts  and  pipe  lines. 
(After  Arnold  and  Garfias.) 

among  the  most  prolific  in  the  United  States,  produce  mainly  oils 
of  medium  to  heavy  grade,  with  asphaltic  base.  The  rocks  con- 
taining the  oils  are  partly  unconsolidated  and  in  most  of  the  oil- 

442 


PACIFIC  COAST  FIELDS  443 

PETROLEUM  MARKETED  IN  CALIFORNIA  IN  1916  AND  1917 


District  and  County 

1916 

1917 

Quantity 
(Barrels) 

Value 

Price 
per 
Barrel 

Quantity 
(Barrels) 

Value 

Price 
per 
Barrel 

Coastal  and  southern: 
Los  Angeles  County: 
Los  Angeles  city  
Montebello 

299,781 

'"168,590 
1,457,471 

1  1,973,882 

$180,386 

'    '89,947 
867,319 

1,336,713 

7,721,779 
705,543 

2,321,186 
29,267 
25,792 

8,460,623 

SO.  602 

'6.828 
0.596 

0.677 

0.638 
0.757 

0.523 
0.693 
0.566 

0.595 

261,348 
829,428 
121,879 
1,170,213 

2,156,655 

14,515,060 
963,422 

4,801,065 
47,036 
98,715 

15,984,766 

$227,572 
860,258 
132,557 
1,177,446 

2,066,484 

14,021,289 
1,044,904 

4,193,557 
42,673 
89,140 

14,211,319 

$0.871 
1.037 
1.088 
1.066 

0.958 

0.966 
1.084 

0.873 
0.909 
0.903 

0  889 

Newhall  .  .  . 

Salt  Lake  
Coyote  Hills  

Puente  

Whiltier 

}l2,095,819 

932,028 

1 
[  4,439,619 

42,223 
45,603 

14,231,251 

Orange  County: 
Coyote  Hills 

Fullerton  
Ventura  County: 
Santa  Paula  

Santa  Barbara  County: 
Lompoc  

Los  Alamos  
Santa  Maria 

Summerland  
Monterey  County 

San  Luis  Obispo  County  
Santa  Clara  County  
San  Joaquin  Valley: 
Fresno  County: 
Coalinga 

Kern  County: 
Kern  River  
Lost  Hills 

8,226,788 
3,433,034 
4,467,668 
31,840,361 
7,357,818 

4,528,711 
1,829,710 
2,692,120 
18,570,505 
4,242,432 

0.550 
0.533 
0.603 
0.583 
0.577 

8,144,348 
4,249,039 
5,024,320 
28,829,674 
6,680,581 

6,998,867 
4,044,013 
3,691,904 
27,095,565 
6,264,216 

0.859 
0.951 
0.734 
0.939 
0.937 

McKittrick  a  
Midway 

Sunset  
Grand  total  

55,325,669 

31,863,478 

0.576 

52,927,962 

48,094,565 

0.908 

90,951,936 

153,702,733 

$0.590 

93,877,549 

$86,161,764 

$0.918 

"Includes  Belridge. 

PETROLEUM  MARKETED  IN  CALIFORNIA,  1908-1917,  BY  COUNTIES,  IN  BARRELS 


Los 

Santa 

Ven- 

San 

Santa 

Year 

Fresno 

Kern 

Angeles 

Orange 

Barbara 

tura 

Mateo 

Clara 

Total 

1908  

10,386,168 

18,132,893 

4,692,495 

3,358,714 

7,816,682 

379,044 

«88 

741 

44,854,737 

1909.... 

14,795,459 

23,831,768 

16,774,195 

«70,  179 

55,471,601 

1910  

18,387,750 

37,896,727 

16,665,678 

&60.405 

73,010,560 

1911  

18,483,751 

45,921,712 

16,708,466 

&20.462 

81,134,391 

1912  

19,911,820 

50,245,255 

"17,  095,  395 

&20,  123 

87,272,593 

1913  

19,302,654 

58,278,966 

20,164.689 

642,216 

97,788,525 

1914  

15,692,733 

62,429,243 

3,150,892113,260,226 

4,363,797 

857,685 

^20,751 

99,775,327 

1915  

12,851,034 

53,886,181 

2,732,250  11,885,150 

4,290,944 

908,359 

<*37,617 

86,591,535 

1916  

14,231.251 

55,325,669 

3,839,724  12,095,819 

4,481,842 

932,028 

&45.603 

90,951,936 

1917  

15,984,766 

52,927,962 

4,539,52314,515,060 

4,848,101 

963,422 

&9£,715 

93,877,549 

"Includes  oil  produced  in  San  Luis  Obispo  County. 
''Production  of  Santa  Clara  and  San  Luis  Obispo  Counties. 
Includes  small  quantity  from  Alaska, 
''includes  Monterey  County. 


444  GEOLOGY  OF  PETROLEUM 

producing  areas,  are  intensely  deformed,  so  that  the  beds  lie  at 
high  angles.  In  some  of  the  districts  the  strata  are  overturned. 
Oil  seeps  are  numerous,  and  asphalt  beds  cover  wide  areas.  In  no 
other  region  in  North  America  is  oil  found  in  commercial  quan- 
tities where  the  structure  is  so  complicated,  nor  are  surface  indica- 
tions so  abundant  in  any  other  American  fields.  In  most  respects 
the  California  fields  resemble  the  fields  of  Europe  and  Asia  more 
closely  than  they  resemble  other  fields  in  America. 

Commercial  quantities  of  petroleum  are  found  in  California  in 
every  important  geologic  formation  from  the  Chico  (Upper  Creta- 
ceous) to  the  Fernando  (Pliocene)  and  also  in  the  Quaternary 
deposits  as  tar  springs  and  asphaltum.  The  principal  formations 
of  the  oil  fields,  in  order  of  age,  are  Jurassic  or  pre- Jurassic  crystal- 
line rocks;  the  Franciscan  (probably  late  Jurassic);  the  Knoxville- 
Chico  rocks  (Cretaceous);  the  Tejon  (Eocene);  the  Sespe  (prob- 
ably Oliogocene);  the  Vaqueros  and  Monterey  (lower  Miocene); 
the  Fernando  or  equivalent  (largely  upper  Miocene  and  Pliocene) ; 
and  the  Quaternary.  Commercial  quantities  of  oil  are  found 
chiefly  in  the  Miocene.1 

Coalinga. — The  Coalinga  oil  district, 2  which  is  the  northernmost 
great  field,  is  an  area  50  miles  long  and  15  miles  wide  lying  along 
the  northeastern  base  of  the  Diablo  Mountains,  in  western  Fresno 
and  Kings  Counties,  on  the  southwest  side  of  San  Joaquin  Valley. 
The  productive  area  of  this  district  is  a  strip  13  miles  long  and  3 
miles  wide  in  the  north  end  of  the  district  and  a  narrow  strip  along 
the  southwest  boundary  along  the  slopes  of  the  Kreyenhagen 
Hills.  The  district  is  an  area  of  Cretaceous  and  Tertiary  strata, 
only  slightly  consolidated,  intricately  folded,  and  not  extensively 
faulted.  The  dominant  structural  feature  is  the  monocline  that 
dips  eastward  from  the  Coast  Range  to  the  valley.  On  this  is 
developed  the  Coalinga  anticline,  and  bordering  it  the  Coalinga 
syncline  and  a  great  monoclinal  area  that  forms  the  west  limb  of 
the  syncline.  The  oil  is  found  principally  near  the  top  of  the  anti- 

JARNOLD,  RALPH  and  GARFIAS,  V.  R. :  Geology  and  Technology  of  the  Cali- 
fornia Oil  Fields.  Am.  Inst.  Min.  Eng.  Bull  87,  p.  405,  1914. 

ARNOLD,  RALPH,  and  ANDERSON,  ROBERT:  Geology  and  Oil  Resources  of 
the  Coalinga  District,  California,  with  a  Report  on  the  Chemical  and  Physical 
Properties  of  the  Oils  by  IRVING  C.  ALLEN.  U.  S.  Geol.  Survey  Bull  398, 
1910;  Preliminary  Report  by  ARNOLD  and  ANDERSON.  U.  S.  Geol.  Survey 
Bull.  357,  1908. 


PACIFIC  COAST  FIELDS 


445 


446 

Alluvium  and  terrace  de- 
posits (Pleistocene  and 
Recent).  1-100+  feet. 


Tulare  formation  (Plio- 
cene-lower Pleistocene). 
3,000+  feet. 


Etchegoin  formation  (up- 
permost Miocene),3,500+ 
feet. 


Jacalitos  f  ormatioTi(early 
upper  Miocene),  3,800=fc 
feet. 


Santa  Margarita  (!)  for- 
mation (upper  middle 
Miocene).  900-1,000+ 
feet. 

Vaqueros      sandstone 
(lower     Miocene), 
feet. 


Tejon  formatlon(Eocene). 
1,850+  feet. 


GEOLOGY  OF  PETROLEUM 


-  Chlco  rocks 
(Cretaceous),  12,800+ 
feet. 


Franciscan  formation 
(Jurassic). 


Sand,  clay,  gravel,  stream  conglomerate,  and  soil. 


Slightly  consolidated,  chiefly  marine  fossiliferous  beds  of  gray 
and  blue  sand,  black  clay,  light  sandy  clay,  pebbly  sand,  and 
gravel,  with  locally  hardened  beds  of  sandstone  and  occasional 
layers  of  siliceous  and  calcareous  shale.  The  upper  third  is 
largely  dark  clay,  the  lower  portion  blue  sand. 


Slightly  consolidated  marine  fossiliferous  beds  of  light-gray, 
greenish-gray,  blue,  and  brown  sand,  clay,  and  fine  gravel,  in- 
terbedded  with  similar  deposits  indurated  into  sandstone, 
shale,  and  conglomerate,  with  some  siliceous  shale. 


North  of  Waltham  Creek :  Marine  fossiliferous  sand,  clay,  gravel, 
and  comminuted  serpentine,  in  part  indurated.  South  of  Wal- 
tham Creek:  White,  purple,  and  brown  siliceous,  calcareous.and 
argillaceous  shales. 

Marine  fossiliferous  gray  sandstone  and  sand  with  minorainounts 
of  conglomerate  and  gravel  and  diatomaceous  and  clay  shale. 


Marine  white  and  brown  diatomaceous  and  foraminiferal  sh 


larine  yellowish,  brown,  and  gray  fossiliferous  and  locally  lig- 
nitic  sandstone  arid  dark  clay,  with  a  local  basal  conglomerate. 


Upper  division.  In  upper  half:  Purplish  siliceous  shale,  dark 
clay  shale,  light-colored  calcareous  shale,  white  and  yellow 
sandstone,  and  a  minor  zone  of  tawny  concretionary  sandstone. 


In  lower  half:  Chiefly  massive  drab  concretionary  sandstone. 
Marine  fossils  of  Chico  (Upper  Cretaceous)  sparingly  through- 
out. 


Alternating  thin,  sharply  defined  beds  of  dark  clay  shale,  sandy 
shale,  iron-gray  and  brownish-gray  sandstone,  and  some  beds 
of  conglomerate  and  pebbly  sandstone;  marine  fossils  of  Chico 
(Upper  Cretaceous)  ago  sparingly  in  upper  portion. 


Coarse,  massive  conglomerate  zone  of  locally  variable  thickness, 
with  large  bowlders  of  pre-Kranciscan  rocks.  1'robably  basal 
conglomerate  of  the  Chico. . 


Thinly  bedded  dark  shnlt-  and  sandstone,  similar  to  that  above, 
but  without  fossils. 


Massive  iron-gray  sandstone. 

Thinly  bedded  dark  shale  similar  to  that  above,  with  some  sand- 
tone  layers. 

Similar  shale  and  sandstone  to  thatof  lower  portion  of  Knoxville, 
fhh-o,  jasper,  and  glaucophano  and  other  schists,  with  inti- 
mately associated  serpentine. 


2000 


4000 


6000  Feet 


FIG.  178. — Generalized  section  of  Coalinga  district,  California.  (After  Arnold.} 


PACIFIC  COAST  FIELDS  447 

cline  and  on  the  monocline.  The  geologic  formations  are  shown 
in  Fig.  178. 

The  oil  is  found  (1)  in  sandy  zones  of  the  purple  shale  of  the 
Chico;  (2)  in  the  porous  sandstone  of  the  Tejon,  which  consists 
mainly  of  diatomaceous  and  foraminiferal  shale;  (3)  in  three  zones 
in  the  Vaqueros,  which  is  the  most  productive  formation  in  the 
area;  (4)  in  the  sandstone  above  the  Tejon  in  the  Santa  Margarita; 
and  (5)  in  the  Jacalitos,  particularly  where  it  rests  on  or  is  near  the 
Tejon.  Arnold  and  Anderson1  consider  the  oil  in  the  Chico  and 
Tejon  to  be  original;  in  the  later  formations  it  has  probably  come 
from  some  outside  source. 

The  oil  is  found  mainly  along  the  Coalinga  anticline  and  in  the 
monocline  in  the  west  part  of  the  area  (Fig.  179).  On  this  mono- 
cline tar  springs  or  oil  seeps  occur  mainly  in  the  Tejon  and  Vaq- 
ueros  and  especially  along  an  unconformity  between  these  two 
formations.  The  bituminous  matter  on  oxidation  and  drying  has 
sealed  up  the  beds  more  or  less  completely,  and  this  has  preserved 
the  oil  remaining.  Where  water  is  present  with  the  oil,  the  .oil 
rises  to  crests  of  anticlines  or  to  the  higher  parts  of  the  monocline. 
Where  the  oil  zone  does  not  carry  water  the  distribution  of  oil 
depends  upon  the  distribution  of  the  rocks  rather  than  on  the 
details  of  structure. 

Where  no  water  exists  in  or  is  associated  with  an  oil  zone,  as 
in  the  deeper  portions  of  the  west  side  of  the  field  and  in  by  far  the 
greater  part  of  the  east  side,  the  structure  apparently  plays  but  a 
minor  part  in  the  accumulation  of  the  oil,  the  presence  or  absence 
of  the  petroleum  in  the  porous  strata  of  the  zone  apparently 
depending  entirely  upon  the  presence  or  absence  of  the  oil-yielding 
shales  of  the  Tejon  (Eocene)  below  or  near  the  porous  strata.  If 
the  Tejon  is  present  under  any  particular  sand  or  zone,  then  the 
abundance  or  scarcity  of  the  oil  depends  largely  upon  (1)  the 
proximity  of  the  particular  sand  to  the  Tejon;  (2)  the  state  of  dis- 
turbance of  the  underlying  shale  of  the  Tejon,  or  its  relative  posi- 
tion (whether  unconformable  or  conformable)  to  the  overlying 
beds;  (3)  the  degree  of  porosity  and  grain  of  the  sands  of  the  zone; 
and  (4)  the  effectiveness  of  the  barriers  hindering  the  escape  of  the 
hydrocarbons  (oil  and  gas)  from  the  oil  sands. 

Within  the  tested  territory  of  the  Coalinga  district  it  has  been 
found  that  the  areas  of  Miocene  sediments  (either  Vaqueros,  Santa 

I0p.  cit.,  p.  183. 


448  GEOLOGY  OF  PETROLEUM 

Margarita  (?),  or  Jacalitos)  immediately  underlain  by  the  shales 


o 


-d 

3. 


of  the  Tejon  are  oil  bearing;  that  the  productiveness  of  these  bed? 


PACIFIC  COAST  FIELDS  449 

varies  roughly  inversely  with  their  distance  from  the  shales  of  the 
Tejon;  that  the  productiveness  is  greatest  where  the  Tejon  occu- 
pies a  position  of  angular  unconformity  with  the  Miocene  sands 
or  is  more  or  less  disturbed,  as  near  the  axis  of  an  anticline  such  as 
the  Coalinga  anticline. 

The  few  small  faults  are  so  situated  as  not  to  affect  the  oil  zones 
greatly,  and  they  are  not  marked  by  the  presence  of  escaping 
hydrocarbons.  There  are  two  types  of  oil,  a  paraffin  oil  which 
appears  to  have  originated  in  foraminiferal  shales  in  the  Upper 
Cretaceous  and  an  asphalt  oil  which  is  believed  to  have  its  original 
source  in  diatomaceous  and  foraminiferal  shales  of  upper  Eocene 
age.  The  former  is  accumulated  in  sandy  zones  interbedded  with 
the  shales  that  are  supposed  to  have  given  rise  to  it;  the  latter, 
which  is  the  chief  product  of  the  district,  is  accumulated  to  some 
extent  in  the  Tejon  formation  but  chiefly  in  sands  of  the  Vaqueros 
(lower  Miocene),  Santa  Margarita  (?)  (upper  middle  Miocene), 
and  Jacalitos  (upper  Miocene)  formations.  The  Vaqueros  is  the 
principal  producer  of  the  district.  The  oil  wells  range  in  depth 
from  600  to  more  than  4,000  feet  and  penetrate  from  20  to  over 
200  feet  of  productive  sands.  The  product  ranges  from  a  black  oil 
of  14°  or  15°  Baume  to  a  greenish  oil  of  35°  Baume  or  lighter.  The 
yield  ranges  from  3  or  4  barrels  a  day  for  individual  wells  in  the 
Oil  City  field  to  as  much  as  3,000  barrels  a  day  for  the  deeper  holes 
in  the  Eastside  field. 

Lost  Hills. — The  Lost  Hills  district1  is  in  Kern  County,  50  miles 
southeast  of  Coalinga.  The  strata  include  the  Santa  Margarita 
(marine),  Jacalitos,  and  Etchegoin,  of  upper  Miocene  age,  and  the 
Tulare,  a*  fresh-water  formation  of  Pliocene  age. 

The  Santa  Margarita  consists  of  a  series  of  diatomaceous  shales 
from  2,000  to  3,000  feet  thick,  the  entire  series  interbedded  with 
fine  sandstone  and  sandy  shales.  It  is  believed  to  be  the  parent 
formation  of  the  oil  in  this  district,  and  the  sandy  members  in  the 
upper  part  of  the  formation  also  act  as  reservoirs  for  the  oil  toward 
the  southern  part. 

Unconformably  overlying  the  Santa  Margarita  is  a  series  of  blue 
clay  shales  interbedded  with  bluish  sands  having  a  total  thickness 
in  this  district  of  over  3,000  feet,  the  whole  believed  to  be  the 
equivalent  of  the  Jacalitos  and  Etchegoin  formations  that  are  well 

ARNOLD,  RALPH,  and  GARFIAS,  V.  R. :  Geology  and  Technology  of  the 
California  Oil  Fields.  Am.  Inst.  Min.  Eng.  Bull.  87,  p.  422,  1914. 


450  GEOLOGY  OF  PETROLEUM 

developed  in  the  Coalinga  district,  to  the  north.  The  Jacalitos 
shales  form  an  impervious  cover  to  the  underlying  oil  reservoirs, 
and  where  the  Santa  Margarita  is  eroded  and  the  oil  is  allowed 
passage  along  the  crest  of  the  anticlinal  fold,  the  sands  at  the  base 
of  the  Jacalitos  become  the  oil  reservoirs.  This  is  the  case  in  the 
northern  part  of  the  district,  where  the  lower  sandy  members  range 
between  75  and  100  feet  thick,  generally  in  two  different  bodies. 

The  Tulare  formation,  300  to  500  feet  thick,  follows  the  topog- 
raphy of  the  region  and  lies  nearly  horizontal  throughout  the  Lost 
Hills  district.  In  the  northern  part  of  the  field  the  oil  from  the 
underlying  formations  has  migrated  upward  and  collected  in  the 
Tulare  in  minor  quantities. 

The  dominant  structural  feature  of  the  Lost  Hills  district  is  the 
Coalinga  anticline,  which  extends  southeastward  from  Anticline 
Ridge,  in  the  Eastside  Coalinga  field,  through  the  Kettleman  Hills 
to  the  Lost  Hills,  where  it  runs  in  a  southeasterly  direction,  finally 
plunging  under  the  valley  filling  with  an  axial  dip  of  about  150 
feet  to  the  mile.  The  folding,  which  has  had  a  controlling  influence 
on  all  the  formations  and  on  the  accumulation  and  migration  of  the 
oil  in  the  district,  has  been  more  or  less  intermittent  along  the 
Coalinga  anticline,  as  is  attested  by  the  unconformable  position 
of  the  Jacalitos  on  the  Santa  Margarita.  The  erosion  which  took 
place  before  the  deposition  of  the  Jacalitos  was  more  intense 
toward  the  northern  part  of  the  district,  thus  exposing  lower 
members  of  the  Santa  Margarita  formation  in  this  direction.  It 
was  from  these  eroded  members  that  the  Santa  Margarita  oil 
migrated  to  the  lower  sandy  beds  of  the  overlying  Jacalitos.  In 
the  southern  part  of  the  district  the  impervious  Santa  Margarita 
shales  were  not  disturbed  or  eroded  to  the  extent  of  allowing  the 
escape  of  the  oil,  which  was  retained  within  its  sandy  members. 
The  gravity  of  the  oil  in  trie  Santa  Margarita  averages  about  35° 
Baume,  while  that  of  the  oil  in  the  base  of  the  Jacalitos,  presum- 
ably also  once  indigenous  to  the  Santa  Margarita,  has  a  gravity  of 
only  18°. 

McKittrick,  Sunset,  and  Midway. — The  McKittrick,  Sunset, 
and  Midway  fields1  are  in  Kern  County,  south  of  the  Coaiinga  dis- 

1  ARNOLD,  RALPH,  and  JOHNSON,  H.  R. :  Preliminary  Report  on  the  McKit- 
trick-Sunset  Oil  Region.  U.  S.  Geol.  Survey  Bull  406,  1910. 

ARNOLD,  RALPH,  and  GARFIAS,  V.  R. :  Geology  and  Technology  of  the  Cali- 
fornia Oil  Fields.  Am.  Inst.  Min.  Eng.  Bull  87,  pp.  383-470,  1914. 


PACIFIC  COAST  FIELDS  451 

trict.  Bakersfield  is  some  40  miles  to  the  east  of  the  oil  fields. 
The  district  mapped  by  Arnold  and  Johnson  is  60  miles  long  and 
30  miles  wide,  and  the  petroleum-bearing  formations  trend  north- 
wset  through  its  entire  length.  The  southern  half  of  the  district, 
however,  supplies  almost  the  whole  output  of  oil  and  includes  the 
Midway  and  Sunset  fields.  Oil  is  produced  also  in  the  Devil's 
Den,  which  adjoins  and  is  a  continuation  of  a  sub-district  of  the 
Coalinga  field. 

The  oil  fields  lie  on  the  east  slope  of  the  Temblor  Range,  which 
rises  some  4,000  feet  above  the  sea.  The  San  Emigdio  Range  lies 
to  the  south,  on  the  border  of  the  Sunset  field.  The  country  is  an 
area  of  hills  and  plains  east  and  north  of  the  mountain  ranges. 

The  Temblor  Range,  which  trends  northwest,  is  a  great  mono- 
cline dipping  northeast  on  which  are  developed  many  minor  folds, 
the  axes  of  which  make  small  angles  with  the  major  range.  In 
general  they  strike  a  few  degrees  more  to  the  west  than  the  major 
monocline.  On  the  southwest  the  Temblor  Range  is  bordered 
by  the  great  San  Andreas  fault  zone,  which  has  been  traced  from 
Point  Arena,  on  the  Pacific  Coast  north  of  San  Francisco,  for  over 
600  miles,  nearly  to  Salton  Sea.1  The  faulting  and  folding  on  the 
side  of  the  range  give  in  effect  a  huge  anticlinorium,  which  is  most 
clearly  shown  in  the  northwestern  part  of  the  area.  There  are 
also  several  smaller  faults  in  the  region,  some  of  them  thrust  faults. 

The  wells  in  the  McKittrick  district,  including  Belridge,  range 
in  depth  from  about  600  to  1,800  feet  or  more.  The  oil  is  dark 
colored,  most  of  it  is  heavy,  from  12°  to  20°  Baume.  The  pro- 
duction from  individual  wells  ranges  from  2  to  1,000  barrels 
a  day. 

The  McKittrick  field2  lies  on  the  flanks  of  three  more  or  less  local 
and  highly  complex  folds  subsidiary  to  the  great  northeastward 
dipping  monocline  of  the  Temblor  Range.  Thrust  faulting  and 
overturning  have  so  complicated  the  folding  as  to  place  the  older 
beds  above  the  younger.  (See  Fig.  64.) 

The  oil  is  believed  to  have  originated  in  the  diatomaceous  shales 
of  the  Monterey  and  Santa  Margarita  formations  and  to  have 
migrated  to  the  porous  layers  intercalated  with  them  or  to  the 


,  A.  C.  :  Report  of  the  Earthquake  Investigation  Committee  on  the 
California  Earthquake  of  April  18,  1906.  Carnegie  Inst.  Washington,  Pub. 
87,  1908. 

ARNOLD,  RALPH,  and  JOHNSON,  H.  R.  :  Op.  tit.,  p.  111. 


452 


GEOLOGY  OF  PETROLEUM 


sands  and  gravels  of  the  unconformably  overlying  McKittrick 
formation. 

There  are  two  productive  zones  in  the  McKittrick  district.  In 
the  northern  part  of  the  district  one  zone,  the  lower  one,  lies  nearly 
horizontal  and  is  usually  between  100  and  240  feet  thick;  in  the 
southern  part  the  zone  is  overturned  and  stands  nearly  vertical. 
The  upper  zone  is  only  moderately  productive.  Where  the  oil 
sand  reaches  the  surface,  west  of  the  town  of  McKittrick,  enormous 
deposits  of  asphalt  have  formed.  The  structure  of  this  area  is 
exceedingly  complicated.  (See  Fig.  180.) 

The  Sunset-Midway  field  has  recently  been  described  by  Pack1 
and  Rogers. 2  The  area  covered  in  their  reports  overlaps  the  area 
mapped  by  Arnold  and  Johnson,  and  extends  farther  southeast. 


FIG.  180. — Ideal  cross-section  of  north  end  of  McKittrick  field,  California. 
The  McKittrick  oil  sand  lies  below  an  overthrust  fault,  A  A.  (After  Arnold 
and  Anderson.) 

The  Tertiary  formations  range  in  age  from  Eocene  to  Pliocene 
and  are  altogether  18,000  feet  thick  (Fig.  181).  They  consist  of 
sands,  gravels,  and  clays,  poorly  consolidated,  and  in  the  central 
part  of  the  section  are  4,800  feet  of  material  of  Miocene  age  that 
consists  largely  of  remnants  of  diatoms.  There  are  numerous 
unconformities  in  the  section. 

The  foothill  region  of  the  Temblor  Range  is  closely  folded  and 
is  faulted.  The  oil,  according  to  Pack,3  originated  in  the  diatc- 
maceous  shale  formations,  chiefly  from  the  alteration  of  organic 

'PACK,  R.  W. :  The  Sunset-Midway  Oil  Field,  California.  U.  S.  Geol.  Sur- 
vey Prof.  Paper  116,  part  1 ;  Geology  and  Oil  Resources,  pp.  1-179,  1920. 

ROGERS,  G.  S.:  The  Sunset-Midway  Oil  Field,  California.  U.  S.  Geol. 
Survey  Prof.  Paper  116,  part  2;  Geochemical  Relations  of  the  Oil,  Gas,  and 
Water,  pp.  1-103,  1919. 

3PACK,  R.  W.:  Op.  tit.,  p.  70. 


PACIFIC  COAST  FIELDS 


453 


matter  contained  in  diatoms  and  foraminifers,  but  probably  in 
part  also  from  the  alteration  of  terrestrial  vegetal  debris. 


Alluvium  and     r 

terrace  deposits  4 

(Recentand  Pleistocene)\ 


PasoRobles("Tulare"; 
formation 


(Pleistocene  ? 
and  Pliocene} 


Etchegoin  formation 

Upper  Miocene)  _ 
As  here  uscd-probably  includes 
e  representative  oftheJacalitos 
formation  at  base 


Maricopa  shale 
(middle  Miocene) 


Vaqueros  formation 
(lower  Miocene;  for  con-. 


Fejon  formation 
(Eocene.) 


Basement  complex 


McKittrick 
group 


In  jdnfmigefto  Mountains  anartoaif 
s  ncfstone  containing  Santa  Margarita 
fc.jna  and  here  designated 
Santa  Margarita  format 
rests  crrrconformao/y  on  the 
and  Tejon  formations 


Monterey 
group 


io,opo  rcei 


FIG.  181. — Generalized  columnar  section  of  the  rocks  in  the  Sunset-Midway 
oil  field  and  in  the  north  flank  of  the  San  Emigdio  Mountains.  Position  of  oil- 
bearing  beds  indicated  by  solid  black.  (After  Pack.} 


454  GEOLOGY  OF  PETROLEUM 

Some  of  the  oil  now  contained  in  the  productive  pools  has 
originated  in  the  part  of  the  region  in  which  these  pools  occur,  but 
much  of  it  has  been  formed  in  the  shale  that  lies  beneath  San 
Joaquin  Valley.  The  oil  has  migrated  from  the  beds  beneath  the 
valley  to  the  foothills  and  collected  in  the  small  anticlines  that 
extend  from  the  hills  out  into  the  valley. 

The  reservoirs  from  which  the  wells  derive  their  oil  are  chiefly 
Miocene  or  Pliocene  sandy  beds  that  rest  unconformably  upon  the 
diatomaceous  shale.  Sandy  lenses  within  the  shale  yield  some 
of  the  oil. 

The  oil-bearing  beds  in  the  late  Tertiary  sequence  are  coarse 
and  fine  sands  that  range  in  thickness  from  a  few  feet  to  a  few 
hundred  feet.  These  beds  crop  out  in  the  foothills  of  the  Temblor 
Range,  and  their  line  of  outcrop  marks  the  western  limit  of  the 
main  productive  field.  Toward  the  east  the  productive  oil  sands 
are  buried  progressively  deeper  beneath  the  surface.  In  the 
eastern  part  of  the  field  the  productive  sands,  which  are  usually 
10  to  50  feet  thick,  are  interspersed  with  barren  beds  of  equal 
thickness  through  a  section  600  to  800  feet  thick.  Near  the  out- 
crop the  total  thickness  of  the  zone  containing  oil  sands  is  rarely 
more  than  200  or  300  feet  but  the  portion  of  it  composed  of  oil  sand 
is  greater  there  than  in  the  parts  of  the  field  where  the  sands  lie 
deeper. 

The  richest  sands  lie  close  to  the  contact  with  the  diatomaceous 
shale.  These  oil-bearing  beds  are,  however,  not  of  the  same  age 
throughout  the  field,  for  the  formation  of  which  they  are  a  part 
rests  unconformably  on  the  shale,  and  younger  beds  that  abut 
against  the  shale  in  the  western  part  of  the  field  are  younger  than 
those  against  the  shale  in  the  eastern  part. 

The  oil  has  evidently  moved  chiefly  through  the  lowest  part  of 
the  formation  that  rests  upon  the  diatomaceous  shale,  as  these 
beds  are  fairly  porous  and  offer  less  resistance  to  the  movement  of 
the  oil  than  the  shale.  The  movement  is  therefore  chiefly  parallel 
to  the  plane  of  unconformity — that  is,  to  the  top  of  the  shale. 
Near  the  outcrop,  either  by  fractionation  or  by  reaction  with 
alkaline  water,  the  oil  becomes  very  viscous  and  seals  the  beds 
through  which  the  oil  is  moving. 

The  tarrification  of  the  oil  is  caused  chiefly  by  the  addition  of 
sulphur  derived  from  the  sulphate-bearing  surface  waters.  In 


PACIFIC  COAST  FIELDS 


455 


places  this  same  reaction  has  caused  the  formation  of  deposits  of 
sulphur. 

When  the  avenue  of  escape  to  the  surface  is  closed  the  oil  moves 
out  from  the  plane  of  unconformity  through  the  more  porous  of 
the  beds  in  the  formation  that  rests  upon  the  shale.  Movement 
in  this  manner  is  rendered  easy  by  the  fact  that  the  younger 
formation  was  laid  down  in  a  transgressing  sea  and  the  different 
beds  in  it  abut  against  the  shale  just  as  horizontal  layers  of  sand 
held  in  a  huge  bowl  would  rest  against  the  sides  of  the  bowl  (Fig. 
182).  The  distance  that  the  sands  which  extend  out  from  the 
unconformity  are  filled  with  oil  is  variable,  but  each  sand  beyond 
the  point  at  which  it  contains  oil,  according  to  Pack,  is  filled  with 
water. 


FIG.  182. — Diagram  illustrating  probable  occurrences  of  water,  oil  and  tar 
sand  in  part  of  Sunset-Midway  oil  field,  California.  Arrows  indicate  direction 
of  movement  of  edgewater.  (After  Pack.) 

Viewed  in  cross-section  the  arrangement  of  the  oil  sands  near  the 
outcrop  may  be  compared  to  a  branch  from  one  side  of  which 
parallel  twigs  extend,  the  oil  sands  along  the  unconformity  being 
the  branch  and  the  oil  sands  in  the  formation  that  rests  upon  the 
diatomaceous  shale  the  twigs  (Fig.  182). 

Along  the  anticlines  that  are  separated  by  synclines  from  the 
outcrop  of  the  oil  sands  the  oil  has  collected  in  sands  that  lie  some 
distance  above  the  plane  of  unconformity  (Fig.  183.)  This  oil 
has  evidently  moved  vertically  through  the  lenticular  sands.  In 
any  sand  that  contains  oil  and  gas  in  these  outer  anticlines  there  is 
a  notable  tendency  for  the  gas  to  occupy  the  higher  parts  of  the 


456 


GEOLOGY  OF  PETROLEUM 


fold  and  the  oil  the  lower  parts  or  saddles  of  the  same  fold.  In 
the  outer  anticlines  dry  gas  has  collected  200  or  300  feet  above 
the  oil. 

In  some  parts  of  the  field  where  the  oil  is  buried  more  than  2,000 
feet  a  zone  of  tar-filled  sand  lies  less  than  1,000  feet  below  the 
surface.  This  zone  is  believed  to  mark  the  place  where  the  upward- 
moving  hydrocarbons  have  met  and  been  oxidized  by  surface 
waters.  The  evidence  indicates  that  these  hydrocarbons  have 
moved  more  or  less  vertically  through  the  intervening  beds.  Pack 
states  that  they  were  probably  in  a  gaseous  state. 

The  gravity  of  the  oil  varies  with  the  grain  of  the  sand,  the  oil 
being  lighter  in  the  fine-grained  beds;  with  the  distance  from  the 


FIG.  183. — Upper  figure  is  a  plan  of  part  of  Sunset-Midway  field,  near  Taft, 
California.  Each  large  square  is  one  square  mile.  Contour  interval  is  250  feet. 
The  lower  figure  is  a  section  on  line  A  A',  a,  Alluvium;  6,  Paso  Robles 
("Tulare")  formation;  c,  Etchigoin  formation  (contains  chief  petroleum 
reservoirs  of  the  district) ;  d,  Maricopa  shale.  (After  Pack.) 

outcrop;  with  the  relation  of  the  oil  to  mineralized  water,  the  oil 
in  contact  with  water  of  certain  types  being  tarry;  and  with  the 
position  on  the  fold,  the  oil  being  lighter  on  the  higher  parts  of  the 
anticline. 

The  oil  ranges  in  gravity  from  less  than  11°  Baume  near  the  out- 
crop to  31°  or  32°  Baume  in  the  part  of  the  field  where  the  oil  comes 
from  great  depths.  The  average  gravity  of  the  oil  obtained  from 
the  sands  near  the  outcrop  is  between  14°  and  18°  Baume;  that  of 
the  oil  obtained  in  the  Buena  Vista  Hills  and  other  parts  of  the 


PACIFIC  COAST  FIELDS  457 

field  where  the  sands  lie  deep  is  21°  to  28°  Baume.  The  oil  nor- 
mally carries  but  little  gasoline,  the  proportion  distilling  at  a  tem- 
perature of  less  than  150°  C.  being  usually  less  than  4  per  cent. 

In  the  Buena  Vista  Hills  the  beds  lying  above  the  oil-bearing 
sands  contain  "dry"  gas  under  heavy  pressure,  commonly  as  much 
as  1,000  pounds  to  the  square  inch  and  in  one  well  reported  to  be 
more  than  2,000  pounds  to  the  square  inch. 

Gasoline  is  "squeezed"  from  the  gas  at  a  number  of  plants  in  the 
field,  and  the  average  amount  recovered  in  1916  was  between  1  and 

3  gallons  from  1,000  cubic  feet  of  gas. 

Kern  River. — The  Kern  River  field  is  in  Kern  County,  about 

4  miles  north  of  Bakersfield,  near  the  southeastern  extremity  of 
San  Joaquin  Valley.1     It  was  discovered  in  1900  and  produced 
18,000,000  barrels  in  1904.     Its  great  production  is  due  to  the 
great  thickness  of  its  sands,  which  range  from  200  to  500  feet. 
The  productive  territory  covers  155  square  miles,  and  its  long  axis 
extends  northwest.     The  productivity  of  the  wells  within  this 
area  varies  with  the  distance  from  the  center  in  a  more  or  less  uni- 
form ratio,  the  more  productive  wells  being  near  the  central  por- 
tion.    The  depth  to  the  productive  oil  sands  ranges  from  400  feet 
on  the  northeast  part  of  the  fold  to  1,100  or  1,200  feet  on  the  south 
and  west  borders.     The  average  depth  of  all  the  wells  is  approxi- 
mately 900  feet,  and  the  gravity  of  the  oil  averages  about  14° 
Baume.     The  oil  is  used  mainly  for  fuel  and  for  the  manufacture 
of  asphalt. 

The  formations  of  the  Kern  River  district  consist  of  a  basement 
of  granitic  rocks  overlain  by  a  series  of  Tertiary  strata  which  attain 
a  thickness  of  about  5,000  feet  in  the  oil  field.  The  granite  of  the 
Sierra  Nevada  is  continuous  around  the  south  end  of  San  Joaquin 
Valley,  and  in  the  vicinity  of  Kern  River  the  escarpment  of  the 
mountain  front  is  believed  to  mark  a  normal  fault  along  which  the 
granite  on  the  east  has  been  raised  and  the  Miocene  beds  on  the 
west  depressed. 

Tertiary  formations  include  an  upper  and  a  lower  division.  The 
upper  division  is  made  up  of  coarse,  unconsolidated  sands,  gravels, 
and  boulders.  These  beds  are  supposed  to  correspond-to  portions 
of  the  Tulare,  Etchegoin,  and  possibly  Santa  Margarita  formations 
of  the  west  side  of  the  valley.  The  lower  division,  composed 

ARNOLD,  RALPH,  and  GARFIAS,  V.  R. :  Geology  and  Technology  of  the 
California  Oil  Fields.  Am.  Inst.  Min.  Eng.  Bull.  87,  p.  436,  1914. 


458  GEOLOGY  OF  PETROLEUM 

mostly  of  clays  and  soft  diatomaceous  shales  grading  up  from  a 
basal  sandstone,  represents  the  Monterey.  The  lower  division  is 
regarded  as  the  source  of  the  oil,  and  the  upper  is  the  main  zone 
of  accumulation. 

There  is,  according  to  Eldridge,1  a  body  of  sands  and  gravels 
from  the  surface  to  varying  depths,  the  maximum,  200  feet.  Be- 
neath this  there  is  usually  a  stratum  of  blue  clay,  which  ranges  in 
thickness  from  a  few  feet  to  100  feet.  This  clay  is  impermeable 
to  the  waters  which  nearly  everywhere  are  present  in  the  sands 
above.  Below  the  clay  is  an  alternation  of  sands  and  clays  with- 
out regularity  and  varying  in  thickness.  These  sands  constitute 
the  oil  reservoirs  of  the  field,  and  as  much  as  400  or  500  feet  of  them 
has  been  encountered  in  a  single  well.  In  a  great  many  wells  200 
or  300  feet  of  oil-bearing  sand  is  found.  Below  the  oil  sands  is 
another  thin  blue  clay.  Although  the  sands  are  exceedingly  irregu- 
lar, the  short  lenses  overlap  and  interlock,  permitting  a  movement 
of  oil. 

The  district  is  a  low  dome  and  presents  a  symmetrical  arrange- 
ment as  regards  its  productive  territory.  Minor  folds  occur 
throughout  the  productive  portion  of  the  monocline,  and  these 
control  accumulation.  The  productive  area  is  an  ellipse.  The 
production  and  quality  of  the  oil  are  best  northeast  of  the  center 
and  gradually  decrease  toward  the  perimeter. 

Santa  Clara.  —  The  Santa  Clara  district,2  in  Ventura  and  Los 
Angeles  Counties,  is  the  oldest  oil-producing  area  in  California. 
This  district  is  in  the  hilly  country  bordering  on  the  Santa  Clara 
Valley,  a  structural  depression  modified  by  erosion.  The  rocks  of 
the  region  are  all  Tertiary  and  Quaternary,  except  a  small  area  of 
pre-Cretaceous  granite  and  gneiss  at  the  southeast  corner. 

The  Tejon,  or  Topatopa  formation,  as  it  is  called  locally,  is  the 
oldest  of  the  sedimentary  series  and  is  of  Eocene  age.  It  consists 
of  3,000  to  possibly  9,000  feet  of  alternating  shale  and  hard  sand- 
stone and  quartzite  and  so  far  has  proved  to  be  the  least  important 
of  the  commercially  productive  oil  formations  in  the  district. 


G.  H.:  Petroleum  Fields  of  California.  U.  S.  Geol.  Survey 
Bull.  212,  p.  310,  1903. 

2ELDRiDGE,  G.  H.  :  The  Santa  Clara  Valley  Oil  District,  Southern  California. 
U.  S.  Geol.  Survey  Butt.  309,  1907. 

ARNOLD,  RALPH,  and  GARFIAS,  V.  R.  :  Geology  and  Technology  of  the  Cali- 
fornia Oil  Fields.  Am.  Inst.  Min.  Eng.  Bull.  87,  pp.  447-452,  1914. 


PACIFIC  COAST  FIELDS  459 

The  Sespe  formation,  supposed  to  be  of  Oligocene  age  and  char- 
acterized by  its  reddish  color  and  wide  distribution  throughout 
the  Santa  Clara  Valley  district,  overlies  the  Topatopa  and  con- 
sists of  about  3,500  feet  of  alternating  hard  sand  and  shale  layers. 
It  has  yielded  oil  of  11°  to  37°  Baume  gravity  and  is  the  chief  pro- 
ducer of  oil  in  the  district. 

The  Sespe  formation  is  conformably  overlain  by  the  Vaqueros 
or  lower  Miocene,  which  consists  of  800  to  3,000  feet  of  dark- 
colored  shale  that  carries' organic  remains  and  minor  amounts  of 
sandstone.  At  most  localities  in  this  region  the  sandstone  mem- 
bers of  this  formation  carry  petroleum,  so  that  the  formation, 
where  available  to  the  drill,  offers  inducements  for  exploitation, 
especially  where  the  structural  conditions  are  favorable. 

The  Monterey  series  (locally  called  the  Modelo),  also  of  lower 
Miocene  age,  overlies  the  Vaqueros  and  consists  of  four  principal 
members  as  follows: 

Feet 

Upper  shale 200  or  more 

Upper  sandstone 100  to  900 

Lower  shale 400  to  1,600 

Lower  sandstone 300  to  1,500 

Certain  beds  have  burned  red  to  considerable  depths  by  fire, 
evidently  supported  by  the  petroleum  they  contained. 

The  lower  sandstone  yields  a  high-grade  oil  in  the  Modelo 
Canyon  wells,  and  at  other  points  throughout  the  series  there  is 
evidence  of  petroleum.  The  lower  shale  is  well  exposed  along  Pole 
and  other  canyons,  where  it  lies  in  sharp  contrast  to  the  upper 
Modelo  sandstone  above  it. 

The  Fernando  formation,  from  5,000  to  8,000  feet  thick,  extend- 
ing from  the  upper  Miocene  to  the  Quaternary,  lies  in  an  uncon- 
formable  position  with  relation  to  the  older  beds,  and  locally  is 
largely  made  up  of  their  waterworh  fragments.  It  is  commonly 
incoherent,  although  in  places  it  contains  layers  of  hard  conglom- 
erate or  sandstone.  The  Fernando  carries  oil  in  the  Newhall  field, 
in  the  region  east  of  Piru  Creek,  and  at  several  isolated  places 
along  the  south  side  of  the  Santa  Clara  River. 

The  general  structure  in  this  district  is  dominated  by  an  over- 
turned anticline,  which  makes  up  the  mountain  range  to  the  north 
parallel  to  the  productive  oil  fields.  The  local  structure  affecting 
the  accumulation  of  oil  in  any  particular  region  is  very  compli- 


460  GEOLOGY  OF  PETROLEUM 

cated,  sharp  folds,  faults,  cross  folds,  and  overturned  folds  being 
common.  These  conditions  account  for  the  lack  of  continuity  of 
the  productive  areas,  particularly  north  of  the  river.  The  struc- 
ture south  of  the  river  is  controlled  by  an  asymmetric  anticline, 
the  axis  of  which  roughly  parallels  the  Santa  Clara  Valley  for  15 
miles.  The  accumulation  of  oil  is  by  no  means  uniform  through- 
out this  fold,  commercial  quantities  occurring  only  in  certain 
favorable  areas  resulting  from  undulations  in  the  fold  itself — for 
example,  in  the  Montebello  and  Bardsdale  fields,  between  which 
are  apparently  unproductive  local  areas.  Owing  to  the  lack  of 
uniformity  in  structural  and  sedimentary  conditions,  the  pro- 
ductive zones  are  encountered  at  varying  depths  and  at  different 
horizons,  and  an  exact  correlation  of  the  zones,  even  in  near-by 
properties,  is  almost  impossible.  This  irregularity  probably 
accounts  also  for  the  diversity  of  the  product  obtained,  the  oil 
ranging  in  gravity  from  10°  to  35°  Baume. 

Seeps  of  oil  and  oil  springs  are  found  at  several  places  in  the 
region.  One  of  the  fault  zones  appears  to  be  marked  by  strong 
seeps.1 

In  Placerita  Canyon,  oil  was  discovered  in  contorted  micaceous 
granitic  schist  that  oyerlies  the  San  Gabriel  granite,  by  miners  who 
were  sinking  a  shaft  to  prospect  for  gold.  Six  wells  are  within 
200  yards  of  the  contact  with  the  Fernando  (Pliocene)  sandstone, 
but  one  is  said  to  be  a  quarter  of  a  mile  away.  The  deposits  are 
unique;  the  oil  probably  occurs  in  the  fractures  of  the  schist.  It 
is  very  light  (50°  to  60°  Baume).  Doubtless  it  has  seeped  into  the 
schist  from  outside  sources. 

Summerland. — The  Summerland  district  is  in  Santa  Barbara 
County,  about  80  miles  northwest  of  Los  Angeles.  The  field  is 
small,  the  producing  wells  being  confined  to  the  vicinity  of  Sum- 
merland, 6  miles  southeast  of  Santa  Barbara.  The  field  is  of  no 
great  importance  economically,  having  produced  from  1895  to 
1906  only  1,373,980  barrels.  In  1899,  its  year  of  maximum  yield, 
it  produced  208,000  barrels.  The  wells  have  small  initial  yield. 
The  oil  is  dark  brown  or  black  and  ranges  in  gravity  from  9°  to 
18°  Baume,  the  average  being  about  14°.  It  is  used  principally 
for  the  manufacture  of  asphalt,  for  fuel,  or  for  road  dressing. 

The  district  is  in  an  area  of  complexly  folded  Tertiary  sediments, 

^LDRIDGE,  G.  H.  '.'Op.  Clt.,  p.  45. 


PACIFIC  COAST  FIELDS  461 

including  about  9,000  feet  of  conglomerate,  sandstone,  and  shale 
of  the  Topatopa  (Eocene);  4,300  feet  of  conglomerate,  sandstone, 
and  shale  of  the  Sespe  (Eocene  or  Oligocene);  2,400  feet  of  sand- 
stone and  shale  of  the  Vaqueros  (lower  Miocene);  1,900  feet  of 
shale  and  volcanic  ash  of  the  Monterey  (middle  Miocene);  1,000 
feet  of  conglomerate,  sandstone,  and  clay  shale  of  the  Fernando 
(upper  Miocene-Pliocene) ;  and  50  feet  of  gravel,  sand,  and  clay  of 
the  Pleistocene — in  all  about  18,650  feet  of  sediments,  practically 
all  of  Tertiary  age.  Unconformities  occur  between  the  Monterey 
and  Fernando  formations  and  between  the  Fernando  and  the 
Pleistocene.1 

The  beds  in  the  vicinity  of  Summerland  dip  south  from  the 
Arroyo  Parida  fault,  which  is  also  the  crest  of  an  anticline.  Small 
folds  are  developed  on  the  south  limb  of  this  anticline  in  the  region 
of  the  oil  wells.  The  Monterey  has  been  eroded  from  the  top  of 
the  anticline.  Resting  unconformably  on  the  truncated  edges  of 
the  Monterey  are  the  Fernando  beds  which  are  steeply  tilted. 

The  oil  wells  are  put  down  on  the  terrace  on  which  the  town  is 
situated,  on  the  beach  in  front  of  this  terrace,  and  on  wharves  that 
extend  out  into  the  ocean,  some  of  them  nearly  a  quarter  of  a  mile. 
They  range  in  depth  from  100  to  more  than  600  feet;  the  shallowest 
are  the  northernmost  wells  on  the  terrace,  the  deepest  those 
farthest  south  on  the  wharves.  The  oil  is  obtained  from  sands 
alternating  with  clay  beds  in  the  Fernando  formation,  which  dips 
almost  due  south  at  angles  ranging  from  nearly  90°  at  the  north 
end  of  the  field  to  nearly  horizontal  at  the  south  end.  Only  one 
productive  sand,  from  10  to  45  feet  thick,  is  penetrated  by  the 
terrace  wells,  but  in  the  wharf  wells  two  or  three  oil  sands  occur. 2 

The  oil  of  the  Summerland  field  has  originated  by  a  slow  process 
of  distillation  from  the  diatoms  and  other  organisms  in  the  Mon- 
terey (middle  Miocene)  shale,  which  is  abundant  in  the  region. 
After  its  formation  quantities  of  the  oil  migrated  upward,  largely 
through  joint  cracks,  under  gas  or  hydrostatic  pressure,  and 
accumulated  in  the  Fernando  formation  in  porous  sandstones 
under  relatively  impervious  clay  layers.  The  oil  did  not  continue 
its  upward  migration  through  the  Fernando  to  the  surface  because 
the  plastic  condition  of  certain  clay  beds  in  that  formation  pre- 

IARNOLD,  RALPH  :  Geology  and  Oil  Resources  of  the  Summerland  District, 
California.     U.  S.  Geol.  Survey  Bull.  321,  p.  21,  1907. 
-Idem,  p.  39. 


462  GECfeQGY  OF  PETROLEUM 


eluded  the  formation  of  cracks  that  could  act  as  channels  for 
the  oil.  In  certain  places,  however,  notably  at  the  north  end  of 
the  field,  the  Fernando  beds  have  been  so  steeply  tilted  that  some 
of  the  oil  has  migrated  along  the  sandy  layers  and  accumulated, 
with  a  loss  of  volatile  constituents,  in  the  unconformably  over- 
lying Pleistocene  sands  and  gravels. 

Santa  Maria. — The  Santa  Maria  oil  district,1  comprising  the 
Santa  Maria,  Lompoc,  and  Arroyo  Grande  fields,  lies  in  the  central 
and  northern  parts  of  the  Lompoc  and  Guadalupe  quadrangles, 
in  western  Santa  Barbara  County,  and  the  southern  part  of  the 
San  Luis  quadrangle,  in  southern  San  Luis  Obispo  County. 

The  area  is  occupied  mainly  by  sedimentary  rocks  thrown  into 
long  and  moderately  gentle  folds  that  trend  principally  northwest 
and  west.  Several  faults  of  small  displacement  trend  nearly 
parallel  to  the  folds.  The  rocks  present  in  the  petroliferous  region 
include  the  Monterey  (middle  Miocene)  diatomaceous  and  clay 
shale,  limestone,  and  volcanic  ash;  Fernando  (Miocene-Pliocene- 
Pleistocene)  conglomerate,  sandstone,  and  shale;  and  Quaternary 
gravel,  sand,  clay,  and  alluvium.  At  the  surface  there  are  oil  and 
tar  seeps,  asphalt,  and  bituminous  shale.  The  asphalt  occurs  as  a 
mixture  of  bituminous  material  with  sand  resulting  from  the 
absorption  by  overlying  sand  deposits  of  seeps  from  the  shale,  as 
hardened  fillings  of  asphalt  in  cavities  along  joints,  and  as  sat- 
urated shale.  The  burnt  shale  is  the  rose-colored  or  slaglike  rock 
observed  within  the  Monterey  shale  at  many  places  in  this  and 
other  oil-bearing  regions.  It  is  the  result  of  the  burning  of  the 
hydrocarbons  that  have  impregnated  the  shale. 

The  wells  range  in  depth  from  1,500  to  more  than  4,000  feet. 
In  the  Santa  Maria  and  Lompoc  fields  they  obtain  their  oil  from 
zones  of  fractured  shale  or  sandy  layers  in  the  lower  portion  of  the 
Monterey  shale.  The  production  of  the  individual  wells  ranges 
from  5  to  3,000  barrels  a  day,  and  the  average  is  between  300  and 
400  barrels.  The  gravity  of  the  oil  ranges  from  19°  to  35°  Baume. 
In  the  Arroyo  Grande  field  the  oil  comes  from  sandstone  at  the 
base  of  the  Fernando  and  has  a  gravity  of  14°. 2 

ARNOLD,  RALPH,  and  ANDERSON,  ROBERT:  Preliminary  Report  on  the 
Santa  Maria  Oil  District.     U.  S.  Geol.  Survey  Bull.  317,  1907. 
ARNOLD,  RALPH,  and  GARFIAS,  V.  R. :  Op.  cit.,  pp.  439-444. 
ARNOLD,  RALPH,  and  ANDERSON,  ROBERT:  Op.  cit.,  p  66. 


PACIFIC  COAST  FIELDS  463 

Concerning  the  relations  of  oil  to  structure  in  this  region,  Arnold 
and  Anderson1  say:  "Although  oil  accumulation  is  affected  by  a 
complication  of  other  circumstances,  the  anticline  seems  to  be  the 
chief  favorable  factor  and  affords  a  tangible  and  fairly  trust- 
worthy clue.  Close  folding  appears  to  play  a  part  in  depriving 
beds  of  their  oil,  and  excessive  disturbance  and  fracturing  is  un- 
favorable to  its  retention.  Furthermore,  the  position  of  the  beds 
in  the  formation  is  regarded  as  important,  since  there  is  less  like- 
lihood that  the  oil-bearing  strata,  which  seem  to  lie  mainly  low  in 
the  Monterey,  were  able  to  retain  their  contents  when  denuded  of 
the  greater  part  of  the  overlying  formation  or  when  themselves 
exposed  or  partially  removed." 

Los  Angeles. — The  Los  Angeles  city  field2  extends  westward  for 
6  miles  from  a  point  about  4^  miles  west  of  the  business  center  of 
Los  Angeles.  It  was  discovered  in  1892  when  a  shaft  was  sunk 
near  a  brea  deposit.  The  wells  are  500  to  1,200  feet  deep  or  more 
and  the  gravity  of  oil  from  12°  to  19°  Baume.  The  wells  are 
small  producers  and  are  pumped.  The  Salt  Lake  field  is  a  few 
miles  west  of  the  city  field.  The  wells  are  between  1,200  and  3,000 
feet  deep,  and  the  average  gravity  of  the  oil  is  between  16°  and  18° 
Baume.  Considerable  gas  under  strong  pressure  accompanies  the 
oil,  which  causes  the  wells  to  gush  during  their  early  life.  Between 
1894  and  1912  the  district,  including  the  Salt  Lake  field,  produced 
38,860,136  barrels. 

Enormous  deposits  of  brea  or  impure  asphalt  have  formed  along 
the  outcrop  of  the  upper  Puente  sand  and  in  the  wash  above  the 
oil  sand.  Some  of  the  oil  has  apparently  risen  through  cracks  in 
the  shaly  beds  above  the  oil  sand  and  has  escaped  to  the  surface. 

The  formations,  in  the  order  of  age,  comprise  more  than  2,000 
feet  of  indurated  sandstone,  believed  to  be  largely  of  Vaqueros 
(lower  Miocene)  age;  about  2,000  feet  of  shale  and  soft,  thin- 
bedded  sandstone  of  Monterey  (Puente),  also  of  lower  Miocene 
age;  pre-Fernando  basalt  and  diabase  intrusions  cutting  the 
Monterey;  3,000  feet  or  more  of  soft,  thin  and  thick  bedded  sand- 

%  lldem,  pp.  29-30. 

2ELDRiDGE,  G.  H.,  and  ARNOLD,  RALPH:  The  Santa  Clara  Valley,  Puente 
Hills,  and  Los  Angeles  Oil  Districts,  California.  U.  S.  Geol.  Survey  Bull.  309, 
p.  138,  1907. 

ARNOLD,  RALPH,  and  GARFIAS,  V.  R. :  Geology  and  Technology  of  the  Oil 
Fields  of  California.  Am.  Inst.  Min.  Eng.  Bull.  87,  pp.  455-458,  1914. 


464 


GEOLOGY  OF  PETROLEUM 


stone,  thin-bedded  shale,  and  heavy-bedded  conglomerate  com- 
posing the  Fernando  formation,  of  upper  Miocene  and  Pliocene 
age;  and  a  capping  of  Pleistocene  gravels  and  sands  of  variable 
thickness.  The  oil  in  the  Los  Angeles  district  is  derived  largely 
from  the  upper  500  feet  of  the  Puente  or  Monterey^and  the  basal 
beds  of  the  Fernando. 

The  most  prominent  structural  feature  in  the  district  is  the  great 
flexure  which  lies  northeast  of  the  business  portion  of  Los  Angeles 
and  trends  N.  60°  W.  This  fold  is  known  as  the  Elysian  Park 
anticline.  This  anticline  (Fig.  184)  is  almost  an  elliptical  struc- 
tural dome,  as  it  appears  to  plunge  at  both  its  northwest  and 
southeast  ends.  Not  far  from  the  northwest  extremity  of  the 


FIG.  184A.— Sketch  of  part  of  Los  Angeles  oil  field,  California,  showing 
position  of  certain  wells  and  of  sections  shown  in  Fig.  184B.  (Data  from 
Eldridge  and  Arnold,  U.  S.  Geol.  Survey.) 

anticline,  where  it  approaches  the  fault  zone  lying  along  the 
southern  base  of  the  Santa  Monica  Mountains,  the  fold  develops 
into  a  fault.  The  City  field  is  developed  in  strata  at  the  top  of  the 
Monterey  and  possibly  the  base  of  the  Fernando  formation,  on  the 
south  limb  of  the  Elysian  Park  anticline.  The  trend  of  the 
productive  belt,  however,  instead  of  conforming  to  the  axis  of  the 
main  fold,  follows  the  strike  of  the  formations  on  the  south  side  of 
a  divergent  subordinate  line  of  disturbance  and  hence  has  a  direc- 
tion about  east.  The  oil  appears  to  have  accumulated  in  the 


PACIFIC  COAST  FIELDS 


465 


466 


GEOLOGY  OF  PETROLEUM 


sands  of  the  southern  limb  of  the  anticline  just  below  the  point 
where  the  steeply  dipping  beds  bend  toward  the  horizontal  before 
passing  over  the  axis  of  the  fold.  The  structure  in  the  Salt  Lake 
field  appears  to  be  that  of  a  minor  flexure  on  the  flanks  of  the  fold 
along  whose  southern  limb  the  other  Los  Angeles  fields  are  situated. 

Puente  Hills.— The  Puente  Hills,1  about  12  miles  southeast  of 
Los  Angeles,  extend  east-southeastward  for  about  22  miles.  This 
region,  which  includes  several  oil  fields,  is  one  of  the  most  persistent 
producers  in  the  State,  having  yielded  40,943,205  barrels  between 
1882  and  1912. 

The  wells  in  the  Whittier  field  are  small  producers  and  range  in 


FIG.  185A. — Sketch  showing  geology  of  Puente  Hills  oil  field,  California. 
(After  Eldridge.)  Sections  along  lines  AB,  CD,  etc.,  arc  shown  on  Fig.  185B. 

depth  from  600  to  3,500  feet,  the  average  depth  being  close  to 
1,650  feet.  The  oil  produced  runs  between  15°  and  24°  Baume. 

The  Coyote  field  is  "deep  territory,"  the  wells  producing  large 
quantities  of  oil  by  natural  flow.  The  average  depth  of  the  wells 
is  about  3,300  feet,  and  the  maximum  about  4,500  feet.  The 
gravity  of  the  oil  is  between  20°  and  33°  Baume.  The  average 
daily  production  per  well  in  the  Whittier  and  Coyote  fields  is  about 
22.8  barrels;  that  of  the  Coyote  field  alone  probably  several  times 

^LDRIDGE,  G.  H.:  The  Puente  Hills  Oil  District,  Southern  California. 
U.  S.  Geol,  Survey  Butt.  309,  pp.  102-137,  1907. 


GEOLOGY  OF  PETROLEUM 


467 


468  PACIFIC  COAST  FIELDS 

this,  as  certain  of  the  wells  produce  from  1,500  to  3,000  barrels 
daily. 

In  the  Puente  field  the  first  well  was  drilled  in  1880,  and  wells 
drilled  in  1886  and  1887  are  still  being  pumped.  The  average 
depth  of  the  wells  in  this  field  is  somewhat  over  1,300  feet;  the 
average  life  has  been  about  16  years;  the  gravity  of  the  oil  ranges 
between  21°  and  32°  Baume.  Individual  wells  yield  an  average  of 
1.4  barrels  a  day. 

The  Olinda  or  Fullerton  field  began  producing  in  1900.  In  the 
Olinda  and  Brea  Canyon  areas  there  is  a  wide  diversity  in  gravity 
and  output  for  the  different  localities.  The  wells  range  between 
1,500  and  3,500  feet  in  depth  and  produce  oil  ranging  in  gravity 
between  15°  and  34°  Baume.  In  certain  areas  great  quantities  of 
gas  containing  commercial  quantities  of  gasoline  are  produced 
with  the  oil,  the  gasoline  being  extracted  by  compression  or  freez- 
ing. The  average  daily  production  per  well  in  this  field  is  about 
71.5  barrels. 

The  rocks  of  the  area  are  folded  and  faulted  Tertiary  sediments 
(Fig.  185,  A  and  B).  The  oldest  formation  is  the  Puente  (Miocene, 
approximately  equivalent  to  the  Monterey  and  Modelo);  this  is 
overlain  by  the  Fernando  (Pliocene)  and  the  Pleistocene  gravel. 
Both  the  Puente  and  the  Fernando  are  productive.  The  Puente 
consists  of  sandstone  and  shale  and  is  unconformable  with  the 
Fernando.  The  dominant  structural  feature  of  the  Puente  Hills 
is  an  anticlinorium,  in  which  the  main  fol(J  trends  N.  65°  W.  The 
axes  of  the  greater  anticlines  are  locally  faulted.  The  conditions 
are  almost  a  repetition  of  those  in  the  McKittrick  district.  The 
oil  fields  of  the  Puente  Hills  have  been  developed  in  the  zone  of 
sharp  crumpling  and  in  proximity  both  to  the  trace  of  the  fault 
and  to  the  line  of  unconformity;  the  most  productive  wells  of  the 
McKittrick  district  have  been  drilled  along  the  fracture  and 
adjacent  to  the  unconformity.  Development  in  the  Puente  Hills 
region  has  been  guided  by  the  numerous  seeps  that  occur  along 
the  belt  of  severely  disturbed  strata,  but  not  all  of  these  have 
proved  reliable  indications  of  large  accumulations  of  oil.  The 
significant  factors  appear  to  be  the  anticlines,  the  sharply  disturbed 
zone  along  the  south  side,  the  fault  that  seems  to  be  located  within 
this  zone,  and  the  unconformity  between  the  Fernando  and  the 
Puente  formations.1 

^LDRIDGE,  G.  H.:  Op.  cit.,  p.  109. 


PACIFIC  COAST  FIELDS  469 

Near  Whittier,  in  the  northwest  end  of  the  Puente  Hills,  the  oil 
seems  to  be  confined  to  the  zone  of  fracturing  and  faulting;  pre- 
sumably the  shattering  of  the  rocks  facilitated  the  accumulation 
of  the  oil  or  permitted  it  to  rise  from  lower  beds. 

References  for  California 

ANDERSON,  ROBERT:  Preliminary  Report  on  the  Geology  and  Possible  Oil 
Resources  of  the  South  End  of  the  San  Joaquin  Valley,  California.  U.  S. 
Geol.  Survey  Bull  471,  pp.  108-136,  1912. 

Preliminary  Report  on  the  Geology  and  Oil  Prospects  of  the 
Cantua-Panoche  Region,  California.  U.  S.  Geol.  Survey  Bull.  431,  pp. 
58-87,  1911. 

—  and  PACK,  R.  W. :  Geology  and  Oil  Resources  of  the  West  Border 
of  the  San  Joaquin  Valley,  North  of  Coalinga,  California.  U.  S.  Geol.  Survey 
Bull.  603,  pp.  1-220,  1915. 

ARNOLD,  RALPH:  The  Petroleum  Resources  of  the  United  States.  Econ. 
Geology,  vol.  10,  .pp.  695-712,  1915. 

Geology  and  Oil  Resources  of  the  Summerland  District,  Santa 

Barbara  County,  California.     U.  S.  Geol.  Survey  Bull.  321,  pp.  1-93,  1907. 

The  Miner  Ranch  Oil  Field,  Contra  Costa  County,  California. 

U.  S.  Geol.  Survey  Bull.  340,  pp.  339-342,  1908. 

and  ANDERSON,  ROBERT:  Geology  and  Oil  Resources  of  the 

Santa  Maria  Oil  District,  Santa  Barbara  County,  California.     U.  S.  Geol. 
Survey  Bull.  322,  pp.  1-161,  1907. 

Preliminary  Report  on  the  Coalinga  Oil  District,  Fresno  and 

Kings  Counties,  California.     U.  S.  Geol.  Survey  Bull.  357,  pp.  1-142,  1908. 

and  JOHNSON,  H.  R. :  Preliminary  Report  on  the  McKittrick- 

Sunset  Oil  Region,  Kern  and  San  Luis  Obispo  Counties,  California.     U.  S. 
Geol.  Survey  Bull.  406,  pp.  1-225,  1910. 

and  GARFIAS,  V.  R. :  Geology  and  Technology  of  California  Oil 

Fields.     Am.  Inst.  Min.  Eng.  Butt.  87,  pp.  383-470,  1914. 

Geology  and  Oil  Resources  of  the  Coalinga  District,  California. 

U.  S.  Geol.  Survey  Bull  398,  pp.  1-354,  1910. 

ELDRIDGE,  G.  H. :  The  Asphalt  and  Bituminous  Rock  Deposits  of  the  United 
States.  U.  S.  Geol.  Survey  Twenty-second  Ann.  Rept.,  part  1,  pp.  209-464, 
1901. 

The  Petroleum  Fields  of  California.     U.  S.  Geol.  Survey  Bull. 

213,  pp.  306-321,  1902. 

and  ARNOLD,  RALPH  :  The  Santa  Clara"  Valley,  Puente  Hills,  and 

Los  Angeles  Oil  Districts,  Southern  California.     U.  S.  Geol.  Survey  Bull.  309, 
pp.  1-266,  1907. 

ENGLISH,  W.  A.:  Geology  and  Oil  Prospects  of  the  Cuyama  Valley,  Cali- 
fornia. U.  S.  Geol.  Survey  Bull.  621,  pp.  191-215,  1916. 

LAWSON,  A.  C. :  Report  of  the  Earthquake  Investigation  Committee  on  the 
California  Earthquake  of  April  18,  1906.  Carnegie  Inst.  Washington  Pub. 
87,  1908. 


470  GEOLOGY  OF  PETROLEUM 

PACK,  R.  W. :  Reconnaissance  of  the  Barstow-Kramer  Region,  California. 
U.  S.  Geol.  Survey  Bull.  641,  pp.  141-154,  1914. 

The  Sunset-Midway  Oil  Field,  California.     Part  1,  Geology  and 

Oil  Resources.     U.  S.  Geol.  Survey  Prof.  Paper  116,  pp.  1-179,  1920. 

and  ENGLISH,  W.  A. :  Geology  and  Oil  Prospects  of  the  Waltham, 

Priest,  Bitterwater,  and  Peachtree  Valleys,  California.     U.  S,  Geol.  Survey 
Butt.  581,  pp.  119-160,  1915. 

PRUTZMAN,  P.  W. :  Production  and  Use  of  Petroleum  in  California  in  1904. 
California  State  Min.  Bur.  Bull  32,  1905. 

ROGERS,  G.  S. :  The  Sunset-Midway  Oil  Field,  California,  Part  2,  Geochem- 
ical  Relations  o£  the  Oil,  Gas,  and  Water.  U.  S.  Geol.  Survey  Prof.  Paper  117, 
pp.  1-103,  1919. 

WATTS,  W.  L. :  Gas  and  Petroleum  Yielding  Formations  of  Central  Valley 
of  California.  California  State  Min.  Bur.  Bull.  3,  1894. 

Oil  and  Gas  Yielding  Formations  of  Los  Angeles,  Ventura,  and 

Santa  Barbara  Counties.     California  State  Min.  Bur.  Bull.  11, 1897. 

—    Oil  and  Gas  Yielding  Formations  of  California.     California 
State  Min.  Bur.  Bull.  19,  1900. 

ALASKA  FIELDS 

Oil  is  found  at  several  places  along  the  Pacific  coast  in  Alaska. 
The  Katalla  field  (Fig.  186)  skirts  the  north  shore  of  Controller 
Bay,  about  30  miles  east  of  the  Copper  River  delta.1  The  rocks 
are  mainly  Tertiary  sandstones  and  shales  that  contain  coal  beds 
and  are  intruded  by  basic  dikes.  Under  the  Tertiary  rocks  are 
graywackes,  shales,  and  igneous  rocks  of  unknown  age.  The  pre- 
Quaternary  rocks  have  a  steep  dip  throughout  the  greater  part  of 
the  region  and  are  folded  and  faulted.  Some  of  the  folds  are 
overturned.  Oil  and  gas  seeps  are  numerous  in  a  belt  about  25 
miles  long  from  east  to  west  and  4  to  8  miles  wide. 

The  oil  of  the  seeps  reaches  the  surface  through  a  variety  of  rocks. 
The  seeps  west  of  Katalla  are  associated  with  metambrphic  rocks, 
the  oil  reaching  the  surface  either  through  the  joints  and  bedding 
or  cleavage  planes  of  the  slate  and  graywacke  or  through  surficial 
deposits  which  probably  overlie  such  rocks.  The  position  of  the 
seeps  with  reference  to  the  structure  is  uncertain.  Those  west  of 
Katalla  are  on  steeply  folded  and  metamorphosed  rocks  in  which 
the  structural  features  have  not  been  determined  in  detail.  Those 
,on  Redwood  Creek  and  Katalla  Slough  are  apparently  near  a  fault. 
The  Burls  Creek  and  Redwood  Creek  seeps  are  near  the  axes  of 

'MARTIN,  G.  C.:  Geology  and  Mineral  Resources  of  the  Controller  Bay 
Region,  Alaska.  U.  S.  Geol.  Survey  Bull.  335,  p.  42,  1908;  Petroleum  Fields 
of  Alaska.  U.  S.  Geol.  Survey  Bull  225,  p.  368,  1904. 


PACIFIC  COAST  FIELDS 


471 


anticlines,  the  Redwood  Creek  anticline  being  probably  broken 
near  or  west  of  its  axis  by  a  fault.  The  upper  part  of  the  valley  of 
Burls  Creek  contains  many  seeps  at  which  the  oil  oozes  directly 


472  GEOLOGY  OF  PETROLEUM 

from  steeply  dipping  shales  that  contain  a  large  amount  of  glau- 
conite  grains,  which  gives  the  rock  a  bright  green  color.  Thin 
sections  show  abundant  casts  of  Foraminifera  and  diatoms. 

The  age  of  the  oil  of  the  Katalla  field  is  not  determined.  It  is 
probably  Tertiary.  Brooks1  suggests  that  the  metamorphic  rocks 
that  have  oil  seeps  may  be  thrust  over  the  younger  petroliferous 
beds.  Several  wells  have  been  drilled,  but  the  production  is  small. 
The  oil  has  a  gravity  of  39°  Baume  and  is  rich  in  gasoline. 

The  Yakataga  field2  (Fig.  186)  lies  about  60  miles  east  of 
Katalla.  Here  a  series  of  seeps  marks  a  zone  about  20  miles  long, 
half  a  mile  to  2  miles  from  the  beach.  So  far  as  determined,  all 
the  seeps  lie  along  a  sharp  anticline  whose  southern  limb  is  about 
vertical  and  whose  northern  limb  dips  inland  at  15°  to  45°.  The 
exposed  rocks  consist  of  sandstone  overlain  by  fine-textured  shale 
of  Oligocene  or  lower  Miocene  age. 

Iniskin  Bay  (Fig.  187)  is  an  indentation  which,  with  Chinitna 
Bay  on  the  north,  blocks  out  an  irregular-shaped  peninsula  on  the 
west  shore  of  Cook  Inlet.  The  shore  line  of  this  peninsula  is 
broken  on  the  southwest  by  two  small  indentations — Oil  Bay  and 
Dry  Bay.  Petroleum  seepages  have  been  found  in  this  field  near 
Iniskin,  Oil,  and  Dry  Bays. 

The  bedrock  of  the  field  is  a  fine-grained  sandstone  with  which 
are  interbedded  clay  shales.  Some  beds  of  conglomerate  occur 
in  the  sandstone,  and  one  of  them  forms  the  basal  member  of  the 
formation  and  near  the  head  of  Iniskin  Bay  rests  on  sheared  igneous 
rocks.  The  sandstone  and  the  associated  sediments,  which  are  of 
Middle  Jurassic  age,  have  a  thickness  of  about  1,100  feet.  They 
are  overlain  by  a  shale  formation  with  intercalated  conglomerate. 
The  seeps  occur  in  the  eastern  limb  of  a  broad  anticlinal  arch  which 
has  been  faulted.3 

Cold  Bay  (Fig.  187)  is  an  indentation  on  the  Pacific  shore  nearly 
opposite  Kodiak  Island.  The  area  is  untimbered  and  consists  of 
hills  rising  less  than  1,000  feet  above  the  sea.  Oil  seeps  occur 
in  a  Middle  Jurassic  series  consisting  of  sandstone  and  shale  with 
a  little  limestone.  This  series  is  underlain  by  Triassic  shales, 

BROOKS,  A.  H. :  The  Petroleum  Fields  of  Alaska.  Am.  Inst.  Min.  Eng. 
Trans.,  vol.  51,  p.  613,  1915. 

"BROOKS,  A.  H. :  The  Petroleum  Fields  of  Alaska.  Am.  Inst.  Min.  Eng. 
Bull.  98,  p.  202,  1915. 

3BROOKS,  A.  H.:  Op.  tit.,  pp.  202-203. 


PACIFIC  COAST  FIELDS 


473 


limestones,  and  cherts  and  overlain  by  Middle  Jurassic  arkose 
conglomerate,  sandstone,  and  shale.  The  youngest  rocks  of  the 
district  are  volcanic,  chiefly  andesites  and  basalts.  The  oil-bear- 
ing member  is  Middle  Jurassic  of  the  same  age  as  that  of  the 


FIG.  187. — Map  showing  location  of  Iniskin  Bay  and  Cold  Bay  oil  fields, 
Alaska.   (After  Brooks.) 


474  GEOLOGY  OF  PETROLEUM 

Iniskin  Bay  field.  The  main  structural  features  are  broad,  open 
folds  whose  axes  parallel  the  coast,  trending  about  northeast. 
The  dips  of  the  strata  in  few  places  exceed  15°. l 

1BriooKS,  A.  H. :  The  Petroleum  Fields  of  Alaska.     Am.  Inst.  Min.  Eng. 
Trans. ,  vol.  51,  p.  015,  1915. 


CHAPTER  XXII 
CANADA  AND  NEWFOUNDLAND 

Oil  and  gas  are  found  at  many  places  in  Canada,1  but  thus  far 
oil  has  been  produced  on  a  considerable  scale  only  in  Ontario.  Gas 
has  been  produced  in  Ontario,  Quebec,  New  Brunswick,  and 
southern  Alberta.  There  is  a  large  area  between  Hudson  Bay  and 
the  Canadian  Rockies,  extending  northward  to  the  Arctic  region, 
over  which  surface  indications  consisting  of  oil  and  gas  seeps  and 


Tcrr  sctnds 


5ca/e0t  'Miles 


FIG.  188.  —  Sketch  map  of  Canada  and  Newfoundland,  showing  occurrences  of 
petroleum,  natural  gas  and  tar  sand.   (After  Clapp.) 

tar  sands  are  found.  This  area  has  yielded  gas  at  several  places 
and  a  little  light  oil  near  Calgary.  It  is  regarded  by  many  as  the 
most  promising  region  in  Canada.  An  oil  seep  has  been  found 
east  of  this  area,  south  of  James  Bay.  Oil  occurs  also  in  eastern 
^LAPP,  F.  G.,  and  others:  Petroleum  and  Natural  Gas  Resources  of  Canada. 
Canada  Dept.  Mines.  .Mines  Branch,  Pub.  291,  2  vols.,  1914. 

475 


476 


GEOLOGY  OF  PETROLEUM 


Canada,  in  Nova  Scotia,  in  New  Brunswick,  and  on  Gaspe  Penin* 
sula,  Quebec.  In  this  region  the  rocks  are  consolidated  Paleozoic 
sediments  and  are  rather  closely  folded  and  faulted  at  many 
places.  The  prospecting  that  has  been  done  has  resulted  in  only 
a  small  production.  Fig.  188  shows  occurrences  of  petroleum  and 
natural  gas  and  of  tar  sands  in  Canada. 

ONTARIO 

Practically  all  the  petroleum  produced  in  Canada  has  come  from 
Ontario,1  from  the  district  lying  between  Lake  Huron  and  Lake 
Erie  (Fig.  189).  Nearly  all  the  Ontario  petroleum  has  come  from 
Lambton  County,  at  the  western  edge  of  this  district,  and  from 
Middlesex  County,  just  east  of  it.  The  principal  structural 
features  are  the  domes  at  Petrolia,  at  Oil  Springs,  and  in  Mosa 


EM  Oil  field 


FIG.  189.  —  Sketch  showing  location  of  oil  fields  and  wells  in  South  Ontario. 
(After  Clapp.)  The  heavy  lines  indicate  lines  of  sections  given  in  Figs.  190 
and  191. 

Township.  The  oil  is  derived  from  the  Delaware  and  the  Onon- 
daga  limestone  of  the  Devonian,  and  a  little  comes  from  the 
Trenton  limestone. 

JBRUMELL,  H.  P.  H.:  Natural  Gas  and  Petroleum  in  Ontario.  Canada 
Geol.  Survey  Ann  Rept.,  vol.  5,  part  Q,  pp.  1-94,  1892. 

STAUFFER,  C.  R.  :  The  Devonian  of  Southwestern  Ontario.  Canada  Geol. 
Survey  Mem.  34,  pp.  1-341,  1915. 

CLAPP,  F.  G.,  and  others:  Petroleum  and  Natural  Gas  Resources  of 
Canada.  Canada  Dept.  Mines,  Mines  Branch,  Pub.  291,  vol.  2,  pp.  172-185, 
1915. 

WILLIAMS,  M.  Y.:  Oil  Fields  of  Southwestern  Ontario.  Canada  Dept. 
Mines  Summary  Rept.  1918,  part  E,  pp.  30-42,  1919. 

WINCHELL,  ALEXANDER  :  Sketches  of  Creation.     Appendix,  New  York,  1870. 


CANADA  AND  NEWFOUNDLAND 


477 


At  Oil  Springs,  Lambton  County,  oil  issues  at  the  surface  along 
Black  Creek  just  north  of  the  springs.  In  1859  attempts  were 
made  to  utilize  oil  which  exuded  from  the  "gum  beds"  that  formed 
in  the  drift.  Wells  were  dug  4  or  5  feet  deep  into  the  gravel,  and 
the  oil  would  flow  into  the  wells.  The  principal  development, 
however,  began  in  1862.  At  first  the  arrangements  were  not 
adequate  to  take  care  of  the  flow.  It  is  estimated  that  5,000,000 
barrels  of  oil  was  carried  off  in  the  streams.  One  well  is  said  to 
have  flowed  6,000  barrels  the  first  day. 

The  production  of  the  Ontario  fields  is  shown  below.  The 
Ontario  oil  is  of  good  grade  but  carries  considerable  sulphur. 
That  of  Petrolia  runs  from  28°  to  31°  Baume  and  that  of  Oil 
Springs  from  35°  to  36°. 

OIL  PRODUCED  IN  ONTARIO,  1918a 
(After  Waddell) 


District 

Gallons 

Barrels  of 
35  Gallons 

Petrolia  and  Enniskillen 

2  291  ,356 

65  467 

Oil  Springs  
Moore  Township 

1  ,563  ,487 
222  834 

44  ,671 
6  366 

Sarnia  Township  

120  ,322 

3,437 

Plympton  Township 

14  409 

411 

Bothwell  
Tilbury  (including  Dover  Township)  
Button 

1  ,019  ,060 
882  ,971 
65  635 

29,116 
25  ,227 
1  875 

Onondaga.        

41  513 

1  ,186 

Belle  River 

15  645 

447 

Mosa  Township 

3  814  591 

108  988 

Thames  vi  lie  .  .  .                 .         .... 

54  972 

1  565 

10,106,615 

288  ,760 

"WILLIAMS,  M.  Y.:  Op.  cit.,  p.  41. 

In  general  the  rocks  of  the  district  dip  at  low  angles.  The  axis 
of  the  Cincinnati  arch  branches  in  Ohio,  as  already  noted;  one 
branch  extends  westward  into  Indiana  and  another  eastward  to 
northeastern  Ohio.  The  eastern  branch  of  the  axis  almost  dis- 
appears in  the  region  of  Lake  St.  Clair,  but  an  axis  of  a  very  gentle 


478 


GEOLOGY  OF  PETROLEUM 


I 

is 

I 

i 


folding  occurs  near  Port  Lambton,  Ontario. 
It  strikes  northeast  and  extends  to  the  Pe- 
trolia  dome,  about  23  miles  distant.  The  dip 
from  Petrolia  to  Port  Lambton  is  600  feet. 
Southeast  of  this  anticline  a  synclinal  axis 
plunges  southwestward  from  a  point  near 
Shetland,  Euphemia  Township,  Lambton 
County,  for  about  30  miles  to  a  point  near 
Wallaceburg,  the  average  dip  being  20  feet 
to  the  mile.  Part  of  this  area  is  shown  on  the 
contour  map,  Fig.  27  (p.  122).  A  generalized 
section  from  a  point  near  Courtright  to 
Whitby,  approximately  along  the  east-west 
line  drawn  on  Fig.  189  is  shown  by  Fig.  190. 

Another  section,  from  Port  Colborne 
northwestward,  crossing  the  section  shown 
by  Fig.  190,  near  Dundas,  is  shown  by  Fig. 
191.  The  direction  of  this  section  is  indi- 
cated on  Fig.  189  by  the  line  drawn  north- 
.  west  ward  through  Port  Colborne,  but  the 
section  extends  northwestward  beyond  the 
area  of  Fig.  189  to  Kincardine,  on  Lake 
Huron.  From  St.  Catharines,  in  the  eastern 
part  of  the  area,  near  Niagara  Falls,  the 
rocks  dip  south  at  low  angles  (see  Fig.  94, 
p.  210),  awa}^ from  the  ancient  rocks  that  are 
extensively  exposed  around  Hudson  Bay,  to 
the  great  Appalachian  geosyncline. 

In  Lambton  and  Middlesex  Counties  oil 
is  found  in  what  is  popularly  called  the  Big 
lime,  Lower  lime,  or  Corniferous  limestone 
of  the  Devonian.  This  limestone  is  subdi- 
vided into  the  upper  or  Delaware  limestone 
and  the  lower  or  Onondaga  limestone.  Oil 
occurs  in  both  divisions.  The  largest  oil 
pools  of  the  Corniferous  occur  at  the  tops  of 
rock  domes,  only  smaller  accumulations  of 
oil  being  found  on  terraces.  Because  erosion 
has  eaten  st  rat  igraphic  ally  deeper  into 
domes  than  elsewhere  the  black  shale  has 


CANADA  AND  NEWFOUNDLAND 


479 


been  stripped  from  nearly  all  the  oil 
fields.  Knowing  this,  drillers  rarely 
continue  drilling  where  black  shale 
is  found  (Fig.  13,  p.  66.) 

The  Petrolia  field  has  been  the 
largest  producing  field  in  Canada 
and  is  still  the  largest  except  Mosa 
Township,  recently  developed.  The 
Petrolia  field  is  a  flat-topped,  ellipti- 
cal dome  whose  longer  axis  extends 
northwest  (Fig.  27,  p.  122).  The  cus- 
tom has  been  to  drill  the  oil  wells 
about  475  to  490  feet  deep.  On 
page  480  is  a  typical  log. 

The  porous  limestone  near  the 
bottom  of  the  wells  supplies  most  of 
the  oil.  Some  oil  is  obtained  also 
from  what  is  known  as  a  "mud 
vein."  On  the  Dennis  property  in 
Petrolia  three  wells  forming  a  tri- 
angle about  150  feet  to  the  side 
pump  oil  from  a  depth  of  459  to  460 
feet,  and  the  pumping  of  any  one 
affects  the  other  two.  That  there  is 
a  porous  horizontal  stratum  con- 
taining free  channels  is  thus  estab- 
lished. The  greatest  production  is 
obtained  from  the  porous  limestone. 

The  Oil  Springs  field  may  be  con- 
sidered the  pioneer  Canadian  oil 
field  and  is  remarkable  not  only  for 
its  large  initial  production,  but  for 
the  size  of  its  present  production, 
considering  its  small  area.  The  rocks 
lie  in  a  typical  eccentric  dome.  The 
oil  production  is  fairly  even  over  the 
dome  except  on  the  northwest  side, 
which  appears  to  be  barren  of  oil  at 
elevations  that  are  productive  else- 
where. 


fi  3 


1? 
II 


ll 
sj 
|j 


O  a 


0  = 

•la 


\& 
If 


480  GEOLOGY  OF  PETROLEUM 

LOG  OF  WELL  ON  LAWSON  PROPERTY,  PETKOLIA 


Thickness 

Depth 

Surface  drift              

Feet 

100 

Feet 

100 

Ipperwash  limestone,  or  "top  rock"  

50 

150 

Petrolia  shale  or  "upper  soap"                        

134 

284 

Widder  beds  or  "middle  lime"  

15 

299 

Olentangy  shale,  or  "lower  soap"  
Delaware  limestone,  or  "lower"  or  "big  lime"  
Onondaga  limestone,  penetrated;  oil-bearing  rock 
reported  to  extend  from  462  to  471  feet 

45 
50 

82 

344 
394 

476 

Oil  Springs  has  produced  oil  from  beds  at  three  different  hori- 
zons, all  of  which,  however,  are  probably  supplied  from  the  deepest 
source.  Surface  oil  or  "gum  beds"  in  low  swampy  areas  early 
attracted  attention.  Today  a  fine  lubricating  oil  is  obtained 
from  wells  that  penetrate  unconsolidated  gravels  just  above  the 
solid  formations. 

The  oil  from  the  gushing  wells  of  the  early  days  came  from  a 
"mud  vein"  or  "crevice"  about  7  to  12  feet  from  the  top  of  the 
Delaware  limestone,  as  stated  by  Williams.  The  main  production 
of  the  present  day  is  from  porous  limestone  100  to  120  feet  below 
the  top  of  the  Delaware. 

The  following  is  a  typical  log: 

Loa  OF  A  WELL  BELONGING  TO  C.  O.  FAIRBANK,  IN  ENNISKILLEN  TOWNSHIP 


Thickness 

Depth 

Surface.  . 

Feet 
76 

Feet 
76 

Petrolia  shale,  or  "upper  soap"  

113 

'       189 

Widder  beds,  or  "middle  lime"  

17 

206 

Olentangy  shale,  or  {  'lower  soap" 

25 

231 

Delaware  and  Onondaga  limestone  penetrated  .... 

163 

394 

Oil  crevice  at  240  feet;  oil  rock  between  331  and 

351  feet 

The  gushing  wells  tapped  a  porous  stratum  from  7  to  12  feet 
below  the  top  of  the  Delaware  limestone.     The  drill  is  said  to  drop 


CANADA  AND  NEWFOUNDLAND 


481 


about  4  inches  in  most  wells  when  this  stratum  is  reached.  The 
"crevice"  apparently  consists  of  a  very  porous  bed  of  limestone, 
in  which  are  numerous  interlacing  channels.1 

The  Mosa  oil  pool,  about  4  miles  northwest  of  Glencoe,  Middle- 
sex County,  produced  more  oil  during  1918  than  any  other  field  in 
Canada.  The  main  oil  production  comes  from  the  crest  of  the 
dome  and  very  few  wells  produce  from  terraces  or  structurally 
lower  portions.  The  porous  oil  stratum  of  the  older  fields  appears 
to  be  absent  in  the  Mosa  field.  The  oil  is  obtained  mainly  from 
the  crevices  or  shattered  zones  in  the  Delaware  formation. 

The  following  log  is  typical  of  the  center  of  the  Mosa  field: 


Thickness 

Depth 

Surface  

Feet 

77 

Feet 

77 

("Soap". 

58 

135 

Petrolia  shale        \  Limestone 

6 

141 

("Soap"  with  streaks 

73 

214 

Widder  beds  or  middle  limestone 

19 

233 

I  "Lower  soap" 

20 

253 

Olentangy  shale     \  Streaks  of  limestone  

4 

257 

(Streaks  of  "soap"  
Delaware  and  Onondaga  limestone  penetrated  .... 
Oil  at  264  feet. 

2 
55 

259 
314 

Oil  in  this  field  generally  occurs  in  the  upper  20  feet  of  the  Dela- 
ware limestone,  but  it  occurs  also  in  a  few  wells  in  the  "middle 
lime"  or  Widder  beds.  2  Fig.  192  shows  a  model  of  this  field. 

As  the  Silurian  produces  gas  from  the  Medina  sand  ("Clinton") 
in  Ohio,  and  as  oil  is  obtained  from  the  Trenton  in  Ohio  and 
Indiana,  the  rocks  below  the  Devonian  have  naturally  been 
regarded  as  possible  sources  of  oil  and  gas  below  the  domes  in 
Lambton  County.  A  well  drilled  on  the  Petrolia  dome  to  a  depth 
of  3,770  feet  has  failed  to  reach  a  productive  stratum.  At  Oil 
Springs,  according  to  report,  some  oil  has  been  obtained  from  the 
Trenton,  but  the  production  is  not  mentioned  by  Williams  in  his 
report,  already  cited,  published  in  1919. 


,  M.  Y.:  Op.  cit.,  p.  34. 
2  WILLIAMS,  M.  Y.:  Op.  cit.,  p.  37. 


482 


GEOLOGY  OF  PETROLEUM 


RECORD  OF  DEEP  WELL  ON  R.  I.  BRADLEY  ESTATE,  PETROLIA  POOL 


Feet 

0-90 
90-330 
330-520 


520-1,210 
1,210-1,640 


Salina. 


Pleistocene Surface 

Hamilton Streaks  of  limestone  and  shale.  .  . 

Onondaga.a Limestones 

Streaks  of  brown,  gray,  and  black 

dolomite 

Salt  strata  and  streaks  of  dolomite .  . 
Salt  strata  and  streaks  of  dolomitic 

limestone 1,640-1,747 

Salt  strata  and  gray  dolomitic  lime 

and  shale 1,747-2,105 

Guelph  and  Niagara  dolomitic  lime- 
stone      2,105-2,380 

Niagara  shale  (red  and  dark) 2,380-2,440 

Clinton Clinton 2,440-2,530 

Medina. .  Red  Medina 2,530-2,805 


Guelph  and  Niagara , 


Utica, 


Trenton. 


Lorraine  shales  (light) 2,805-3,010 

Utica  shales  (dark) 3,010-3,175 

Trenton 3,175-3,345 

Birdeye 3,345-3,460 

Chazy  (Canadian) 3,460-3,770 


'Probably  includes  Delaware  formation. 


FIG.  192.— Model  of  Mosa  oil  field,  Ontario,  representing  the  top  of  the 
Delaware  (Corniforous)  limestone.  The  edges  of  the  cardboard  used  in  making 
the  model  may  be  considered  as  lines  of  equal  elevation  or  contour  lines. 
The  wells  are  marked  by  pins  and  beads  represent  the  oil  wells  producing  in 
October,  1918.  (After  Williams.) 


Two  wells  about  40  miles  southwest  of  Petrolia,  in  Kent  County, 
Dover  West,  obtained  oil  from  the  Trenton. 

In  the  second  producing  well  the  main  oil  and  gas  appear  to  be 


CANADA  AND  NEWFOUNDLAND  483 

floating  on  salt  water,  as  considerable  salt  water  is  produced  with 
the  oil.1 

No  gas  is  produced  from  the  "Clinton"  in  Lambton  County. 
East  of  the  Mosa  field  there  is  a  broad,  shallow  syncline,  and  still 
farther  east  the  rocks  rise  to  the  northeast  on  a  broad,  low  anti- 
cline2 that  plunges  southwest.  On  the  flank  of  the  anticline  near 
Port  Colborne  (see  Fig.  191)  gas  is  obtained  in  the  "Clinton" 
sand,  and  gas  wells  are  found  at  several  places  as  far  west  as  90 
miles  west  of  Niagara  Falls. 

NOVA  SCOTIA 

In  Nova  Scotia,  according  to  Brumell, 3  oil  is  frequently  seen  on 
the  waters  of  Lake  Ainslee.  The  oil-bearing  strata  are  so  compli- 
cated by  folding  and  faulting  that  conditions  are  not  favorable  for 
accumulation. 4 

NEW  BRUNSWICK 

In  New  Brunswick  oil  seeps  are  found  in  the  Albert  shales,  and 
albertite  has  been  mined  in  large  quantities.  Although  many 
wells  have  been  drilled  the  amount  of  oil  produced  is  very  small. 
Pools  of  gas  have  been  developed  and  have  supplied  several  towns 
in  New  Brunswick.  The  most  important  of  these  is  the  Stony 
Creek  field,  where  the  rocks  are  of  Paleozoic  age.  Where  the 
Devonian  and  lower  Carboniferous  rocks  abut  against  the  pre- 
Cambrian  rocks  in  Albert  and  Kings  Counties,  they  dip  steeply  to 
the  north,  but  this  inclination  flattens  out  northward  and  the 
middle  Carboniferous  rocks  of  the  central  basin  are  thrown  into  a 
system  of  gentle  folds.  The  Stony  Creek  field  is  about  9  miles 
south  of  Moncton  and  about  4  miles  north  of  Hillsboro.  The 
oil  and  gas  are  found  in  sands  of  the  Albert  series. 

The  sands  are  reported  to  be  dry  of  water,  and  the  gas  has  col- 
lected in  them  at  points  of  local  undulations.5  The  oil  is  a  clear 
dark-green  oil  of  39°  Baume.  The  gas  is  a  wet  gas,  estimated  to 
contain  half  a  gallon  of  gasoline  to  1,000  cubic  feet.6 

WILLIAMS,  M.  Y  :  Op.  cit.,  pp.  39-40. 
2STAUFFER,  C.  R.:  Op.  cit.,  outline  map. 

BRUMELL,  H.  P.  H. :  Petroleum  and  Natural  Gas  in  Canada.     Geol.  Soc. 
America  Bull,  vol.  4,  pp.  225-240,  1893. 
4CLAPP,  F.  G.:  Op.  ait.,  vol.  2,  p.  5,  1915. 
&CLAPP,  F.  G.:  Op.  cit.,  vol.  2,  p.  45. 
6Idem,  p.  48. 


484 


GEOLOGY  OF  PETROLEUM 


GEOLOGIC  COLUMN  FOR  EASTERN  ALBERT  COUNTY,  NEW  BRUNSWICK 

(After  Clapp) 


Age 

Series 

Thickness 
(Feet) 

Character 

Middle  Car- 
boniferous. 

Millstone  grit  (Potts- 
ville). 

500 

Gray  quartz  conglomerate 
and  freestone  with  coal 
streaks. 

Lower  Car- 
boniferous 
(M  a  u  c  h 
Chunk  and 
Pocono). 

Upper   conglomerate 

1  ,950 

Red  and  gray  conglomerate, 
gray  limestone  and  gyp- 
sum. 

Red  shale. 

450 

Red  and  gray  calcareous 
shale  with  thin  sand  and 
conglomerate. 

Lower  sandstone  and 
conglomerate. 

700. 

Gray  micaceous,  and  petro- 
liferous sandstone  with 
some  reddish  conglom- 
erate. 

Lower  Carbon- 
iferous or  De- 
vonian. 

Albert. 
Basal  conglomerate. 

850 
200 

Gray  and  brown  calcareous 
or  bituminous  shales  and 
sands. 
Greenish  conglomerate  with 
slate  fragments,  etc.,  often 
absent. 

QUEBEC 

Gaspe,  the  most  northeasterly  county  of  the  peninsula  of  Gaspe  > 
is  the  only  county  in  Quebec  that  has  produced  oil  in  commercial 
quantity,  and  this  field  was  never  profitable.1  The  total  produc- 
tion is  about  2,000  barrels.  The  country  is  an  area  of  Paleozoic 
limestones,  sandstones,  slates,  and  shales,  thrown  into  sharp  folds, 
locally  almost  on  edge,  the  dips  ranging  from  10°  to  80°.  These 
strata  are  cut  by  igneous  intrusions.  The  anticlines  expose  Silu- 
rian and  Devonian  limestone,  and  the  flanks  of  the  anticlines  and 
synclines  expose  the  Gaspe  sandstone,  which  is  Devonian.  Oil 
seeps  are  numerous,  and  many  wells  have  been  drilled,  some  of 

^LAPP,  F.  G.:  Op.  cit.,  vol.  2,  p.  64. 

MALCOLM,  WYATT:  The  Oil  and  Gas  Fields  of  Ontario  and  Quebec.  Canada 
Geol.  Survey  Mem.  81,  pp.  92-238,  1915: 


CANADA  AND  NEWFOUNDLAND  485 

them  to  great  depths.  The  wells  drilled  on  anticlines  found  no 
oil,  all  the  productive  wells  being  in  synclines.  This  seems  to  be 
an  indication  that  the  breaking  of  the  strata  has  long  ago  caused 
leakage  of  most  of  the  oil.1  The  oil  from  sandy  portions  of  the 
strata  is  of  a  light  amber  color;  that  from  the  lower  Calciferous 
rocks  is  a  heavier  dark  oil.2 

WESTERN  CANADA 

A  large  area  in  western  Canada  and  the  United  States,  east  of 
and  in  the  Rocky  Mountains,  exhibits  indications  of  petroleum. 
(See  Fig.  188,  p.  475.)  The  rocks  exposed  are  largely  of  Cretaceous 
age.  The  Cretaceous  formations  carry  oil  in  Wyoming,  Colorado, 
and  Montana  and  have  yielded  some  oil  at  Calgary,  in  Alberta. 
The  Cretaceous  yields  gas  also  in  Alberta  and  contains  a  very 
extensive  body  of  tar  sands  on  the  Athabasca  River.  The  Upper 
Cretaceous  formations  of  southern  Alberta  are  shown  in  the  table 
below,3  together  with  correlations  of  formations  in  Manitoba, 
Montana,  and  South  Dakota. 

This  great  area  is  underlain  at  many  places  by  the  Dakota  sand- 
stone. This  formation  carries  artesian  water  in  a  large  part  of  the 
plains  region  east  of  the  Rocky  Mountains  and  has  been  encoun- 
tered in  many  wells.  It  is  so  extensive  and  its  position  is  known 
at  so  many  places  that  it  has  served  as  a  key  rock  to  plot  the 
structure  over  a  wide  area.  A  paper  by  Darton4  recently  issued 
shows  by  contours  the  structure  of  a  large  portion  of  the  area  in  the 
United  States,  embracing  parts  of  Kansas,  Colorado,  Nebraska, 
Wyoming  and  South  Dakota. 

In  western  Canada  the  Dakota  sandstone  is  extensively  devel- 
oped in  Manitoba,  Saskatchewan,  and  Alberta.  A  little  oil  has 
been  found  in  Canada  in  a  sand  that  has  been  classed  by  some  as 
Dakota  and  by  others  as  the  Cloverly,  above  the  Dakota.  The 
Cretaceous,  in  or  near  jjie  Dakota,  carries  gas  at  Bow  Island,  at 
Viking,  and  at  Pelican,  Alberta.  The  tar  sands  of  the  Athabasca 
River  are  in  the  Dakota.  The  Dakota  crops  out  at  many  places 

'CLAPP,  F.  G.:  Op.  tit.,  p.  68. 

*Idem,  p.  69.  ELLS,  R.  W. :  The  Oil  Fields  of  Gaspe.  Canada  Geol.  Survey 
Fifteenth  Ann.  Rept.,  new  ser.,  p.  362A,  1903. 

3DowLiNG,  D.  B.:  Correlation  and  Geologic  Structure  of  the  Alberta  Oil 
Fields.  Am.  Inst.  Min.  Eng.  Trans.,  vol.  51,  pp.  353-363,  1915. 

BARTON,  N.  H.:  The  Structure  of  Parts  of  the  Central  Great  Plains. 
U.  S.  (leol.  Survey  Bull.  691,  pp.  1-26,  1919. 


486 


GEOLOGY  OF  PETROLEUM 


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487 


Contours  indicate  the  elevation 
of  the  Dakota  sandstone  with 
reference  to  sea  level.  Heavy  black 
Una  show  the  outcrop  of  Hie 
Dakota  sandstone. 


FIG.  193. — Map  showing  generalized  structure  of  the  Dakota  sandstone  in 
the  United  States  and  Canada  east  of  the  Rocky  Mountains,  with  relation  to 
the  oil,  gas,  and  water  reservoirs.  Sections  along  lines  A-B,  etc..  are  given  on 
Figs.  194-197.  (After  Huntley.) 


488 


GEOLOGY  OF  PETROLEUM 


along  the  mountain  front  and  almost  continuously  along  the 
eastern  edge  of  the  structural  basin.  It  is  represented  as  a  heavy 
black  line  in  Fig.  193.  Over  most  of  the  area  it  is  covered  by 
later  beds  of  Cretaceous  and  Tertiary  age.1  The  principal  forma- 


FIG.  1  94.— Section  along  line  CD,  Fig.  193. 

tions  are  shown  in  the  section  on  p.  490.     The  symbols  in  the 
second  column  correspond  to  those  used  in  Figs.  194  to  197. 

The  beds  form  a  huge  synclinorium  on  which  many  large  anti- 
clines are  superimposed.  These  conditions  are  illustrated  by  the 
contours  in  Fig.  193,  p.  487.  The  synclinorium  is  comparable  to  the 
Appalachian  synclinorium  (see  Fig.  93),  but  the  folds  are  generally 
of  greater  amplitude.  Unlike  the  sands  of  the  West  Virginia- 
Pennsylvania  region  the  Dakota  formation  is  generally  a  contin- 
uous sheet  rather  than  a  group  of  more  or  less  isolated  lenses.  It 


FIG.  195.— Section  along  line  AB,  Fig.  193.     (After  Huntley.) 


is  possible,  however,  that  some  of  the  sand  mapped  as  Dakota  in 
this  region  is  of  Kootenai  age. 

^UNTLEY,  L.  G. :  Oil,  Gas,  and  Water  Content  of  Dakota  Sand  in  Canada 
and  United  States.     Am.  Inst.  Min.  Eng.  Trans.,  vol.  52,  pp.  329-345,  1915. 


CANADA  AND  NEWFOUNDLAND 


489 


FIG.  196. 

Section  along  line  EF,  Fig.  193. 
(A/ter  Huntley.) 


FIG.  197. 

Section  along  line  GH,  Fig.  193. 
(After  Huntley.) 


490 


GEOLOGY  OF  PETROLEUM 


Except  in  northern  Alberta,  the  Dakota  sandstone  contains 
generally  a  fresh-water  fauna.  In  northern  Alberta  marine  and 
brackish-water  conditions  prevailed  when  it  was  laid  down. 
Nearly  everywhere  above  the  Dakota  is  a  great  thickness  of  Cre- 
taceous shales,  largely  marine.  In  southern  Montana  and  Wyom- 


Lower   Ter- 
tiary. 

5bl 

Laramie  —  Paskapoo  series. 

Fresh-water    sands,    clays, 
and  shales. 

Upper  Creta- 
ceous. 

5a 

Laramie  —  Edmonton  series 
(coal  bearing). 

Sand  and  shales. 

6 

Bearpaw  (Pierre-Fox  Hill). 

Gray-brown    shales,    sand 
shells. 

7a 

Belly  River  and  Lower  Dark 
shales. 

Sand  and  shale  in  upper  por- 
tion, black  shale  below. 

Niobrara  (cardiom). 

Sand  lenses  and  dark  shales. 

Benton. 

Black  and  gray  shales. 

Kd 

Dakota  sandstone. 

Soft,  porous  sand  (250  to 
950  feet),  conglomeratic 
at  base. 

Lower  Creta- 
ceous. 

8 

Kootenai  shales  (coal  bear- 
ing). 

Devonian. 

15 

Devonian. 

Limestones,  shale,  and  salt 
or  gypsum. 

Cambrian. 

18 

Cambrian. 

Reddish  sand  and  shales. 

Archean. 

23 

Laurentian. 

Granite. 

ing  the  overlying  shales  include  a  number  of  sands,  some  of  which 
have  yielded  oil  and  gas.  Among  these  are  the  Shannon  sand  of 
the  Pierre  and  the  Wall  Creek  sand  of  the  Benton  in  the  Salt  Creek 
and  Powder  River  pools  in  Wyoming;  and  the  Frontier,  Torch- 
light, Peay,  Cloverly,  and  Greybull  sands  in  the  Big  Horn  Basin. 


CANADA  AND  NEWFOUNDLAND  491 

The  gas  pool  in  the  vicinity  of  Bow  Island,  in  southern  Alberta, 
has  yielded  a  large  production.  The  gas  is  used  at  Medicine  Hat 
and  Leth  bridge.  The  total  capacity  of  the  wells  was  estimated  to 
be  75,000,000  cubic  feet  a  day.  A  well  drilled  5  miles  north  of 
Viking,  Alberta,  obtained  a  considerable  flow  of  gas. 

Gas  was  encountered  at  Pelican  Rapids  in  1897-98.  The  gas 
escapes  with  a  roaring  noise  through  a  4-in.  pipe.  For  many  years 
the  noise  was  so  great  that  it  could  be  heard  at  a  distance  of  2  miles 
or  more,  especially  in  the  winter.  After  nine  years  the  pressure 
appeared  to  be  lessening.1 

So  far  as  is  indicated  by  available  analyses2  the  gases  of  Alberta 
fields  are  "dry."  They  are  composed  essentially  of  methane  and 
nitrogen. 

Fig.  198  is  a  sketch  of  part  of  the  foothill  region  of  southern 
Alberta.  3  Sections  are  shown  in  Fig.  199. 

The  interest  shown  in  the  fields  of  western  Canada  is  due  largely 
to  the  presence  of  the  "tar  sands"  on  the  Athabasca  River.  These 
sands  constitute  one  of  the  largest  deposits  of  asphaltic  material 
known,  if  not  the  largest.  They  crop  out  along  the  river  for  100 
miles  and  occupy  an  area  estimated  to  cover  2,000  square  miles  or 
more.  They  were  deposited  on  an  irregular  floor  and  range  in 
thickness  from  13  to  200  feet.4  The  sands  are  at  the  base  of  the 
Cretaceous  (Dakota)  and  rest  on  Devonian  limestones.5  The 
sands  are  either  white  or  reddish.  At  some  places  they  are  inco- 
herent; at  others  they  are  cemented  by  a  calcareous  matrix.  The 
tar-sand  formation  grades  up  into  a  light-green  sandstone  with 
which  are  commonly  interstratified  thin  bands  of  light-green  shale. 
The  shale  covers  the  sands  where  it  has  not  been  eroded.  The 
sands,  which  are  saturated  with  asphaltum  and  heavy  oil,  are  said 


ROBERT:  The  Tar  Sands  of  the  Athabasca  River,  Canada.  Am. 
Inst.  Min.  Eng.  Trans.,  vol.  38,  p.  843,  1907. 

2CLAPP,  F.  G.  :  Op.  cit.,  vol.  1,  p.  64  and  table  opposite  p.  62,  1914. 

3DowLiNG,  D.  B.  :  Correlation  and  Geologic  Structure  of  the  Alberta  Oil 
Fields.  Am.  Inst.  Min.  Eng.  Trans.,  vol.  51,  pp.  353-363,  1915. 

4CLAPP,  F.  G.:  Op.  cit.,  vol.  2,  p.  237,  1915. 

5McCoNNELL,  R.  G.  :  Report  on  an  Exploration  in  the  Yukon  and  McKenzie 
Basins.  Canada  Geol.  Survey  Rept.,  new  ser.,  vol.  4-D,  pp.  1-163,  1889; 
Report  on  a  Portion  of  the  District  of  Athabasca,  Comprising  the  Country 
Between  Peace  River  and  Athabasca  River  North  of  Lesser  Slave  Lake. 
Canada  Geol.  Survey  Rept.,  new  ser.,  vol.  5-D,  pp.  1-67,  1891. 


GEOLOGY  OF  PETROLEUM 


\  S/-  \ 


CANADA  AND  NEWFOUNDLAND  493 

legentt 


494  GEOLOGY  OF  PETROLEUM 

to  contain  14  gallons  of  oil  to  the  ton.1  According  to  Bell2  the 
petroleum  that  saturated  the  Cretaceous  sand  came  up  from  the 
Devonian  limestones  on  which  it  rests.  Hardened  tar  or  pitch 
may  be  seen  in  the  cracks  and  joint  planes  of  these  limestones, 
showing  that  petroleum  has  passed  through  them  at  a  remote 
period.  The  numerous  exposures  of  Devonian  limestone  seen 
under  the  tar  sands  show  little  evidence  of  containing  bitumen, 
except  as  black  incrustations  in  joint  planes,  cracks,  and  vugs. 
The  tar  may  have  come  from  a  lower  formation,  but  it  is  so  gener- 
ally diffused  in  the  sand  that  it  probably  came  from  the  formation 
immediately  below  it. 3 

Additional  References  for  Canada 

BOSWORTH,  T.  O. :  The  Oil  Fields  of  Western  Canada.  Petroleum  World, 
vol.  12,  pp.  85-92,  1915. 

CAMPBELL-JOHNSTON,  R.  C. :  Suggested  Origin  of  the  Petroleum  Occurring 
in  Western  Canada.  Min.  Jour.,  vol.  108,  pp.  183,  205-206,  1915. 

CUNNINGHAM  CRAIG,  E.  H. :  The  Alberta  Oil  Fields.  Canadian  Min.  Jour., 
vol.  36,  pp.  26-28,  1915. 

The  Prospective  Oil  Fields  of  Western  Canada.     Inst.  Petroleum 

Tech.  Jour.,  vol.  1,  pp.  127-138,  1915;  discussion,  pp.  138-145;  Petroleum  Rev., 
vol.  32,  pp.  82,  102,  1915;  Petroleum  World,  vol.  12,  pp.  75-80,  1915. 

The  Puzzle  of  the  Calgary  Field.  Petroleum  World,  vol.  12, 
pp.  335-336,  1915. 

DELURY,  J.  S. :  The  Principles  Underlying  the  Occurrence  of  Oil  and  Gas 
and  their  Application  to  Western  Canada.  Canadian  Min.  Jour.,  vol.  36,  pp. 
331-333,  1915. 

DICKIE,  F.  J.:  Gas  Fields  of  Alberta,  Canada.  Oil  and  Gas  Man's  Mag., 
vol.  10,  pp.  37-38,  1915. 

BOWLING,  D.  B. :  Correlation  and  Geological  Structure  of  the  Alberta  Oil 
Fields.  Am.  Inst.  Min.  Eng.  Bull.  102,  pp.  1,355-1,364,  1915. 

: Structural  Features  of  the  Alberta  Oil  Fields.  Canadian  Min. 

Jour.,  vol.  36,  pp.  335-336,  1915. 

Structural  Geology  of  the  Alberta  Oil  Fields.     Canadian  Min. 

Inst.  Trans.,  pp.  182-191,  1915;  Canadian  Min.  Inst.  Bull.  35,  pp.  164-172, 
1915. 

HUNTLEY,  L.  G.:  The  Oil  Fields  of  Calgary.  Petroleum  World,  vol.  12,  p. 
247,  1915. 

'BELL,  E.  C. :  Geology  and  History  of  Canadian  Fields.  Oil  and  Gas  Jour. 
Suppl,  May,  1919. 

2BELL,  ROBERT:  The  Tar  Sands  of  the  Athabasca  River,  Canada.  Am. 
Inst.  Min.  Eng.  Trans.,  vol.  38,  p.  838,  1907;  Canada  Geol.  Survey  Rept. 
Prog.,  1882-1884,  part  CC;  also  Summary  Rept.  for  1889,  pp.  103-110. 

3BELL,  ROBERT:  Op.  cit.}  p.  843. 


CANADA  AND  NEWFOUNDLAND  495 

HUNTLEY,  L.  G. :  Oil,  Gas,  and  Water  Content  of  Dakota  Sand  in  Canada 
and  United  States.  Am.  Inst.  Min.  Eng.  Bull.  102,  pp.  1,333-1,  353,  1915; 
discussion,  Bull.  108,  pp.  2,428-2,430,  1915. 

JOHNSON,  H.  R. :  Preliminary  Notes  Upon  the  Geology  of  Western  Alberta 
and  Southeastern  British  Columbia.  Oil  Age,  vol.  11,  February,  1915;  pp.  6-7; 
March,  1915,  pp.  6-8. 

KEMPHER,  L.  S. :  Notes  on  the  Geology  of  Part  of  Southern  Alberta.  Mine, 
Quarry,  and  Derrick,  vol.  1,  pp.  8-10,  1915. 

MALCOLM,  WYATT:  The  Oil  and  Gas  Fields  of  Ontario  and  Quebec.  Canada 
Geol.  Survey  Mem.  81,  1915. 

STAUFFER,  C.  R. :  The  Devonian  of  Southwestern  Ontario.  Canada  Geol. 
Survey,  Mem.  34,  1915. 

TYRRELL,  J.  B. :  Oil  Possibilities  of  British  Columbia.  Am.  Inst.  Min.  Eng., 
Bull.  108,  pp.  2,432-2,433,  1915. 

WILLIAMS,  M.  Y. :  Arisaig-Antigonish  District,  Nova  Scotia.  Canada  Geol. 
Survey  Mem.  60,  1915. 

NEWFOUNDLAND 

Oil  seeps  have  been  known  on  the  west  coast  of  Newfoundland 
for  many  years.  A  well  sunk  in  1867  to  a  depth  of  700  feet 
obtained  traces  of  oil.  A  well  sunk  in  1895  struck  oil  at  700  and 
900  feet  and  a  larger  flow  at  1,230  feet.  The  beds  are  Ordovician 
shales  and  sandstones  with  some  limy  layers.  They  dip  eastward, 
away  from  the  pre-Cambrian  rocks  across  the  bay.  The  wells 
are  sunk  in  the  Ordovician  where  the  strata  are  highly  folded  and 
faulted  and  at  many  places  mashed  and  on  edge. 


496 


GEOLOGY  OF  PETROLEUM 


La.. 

>  *'       °-^J?"^-^ 

\       TepeUiniluXtA 


i: 

M«co,^ 
Abir"l»*.^ 


LEGEND 

—  Pipe  Lines  Completed  ^  =  ^.Buikling 
M^M. Ruili'oads Completed   »«, «« Survcyedor  Building / 

• Pipe  Lines  Paralleled,  by  Railroads 

Barge  Routes 


FIG.  200  — Sketch  map  of  the  northern  Vera  Cruz  oil  region,  Mexico,  show- 
ing pipe  lines  and  railroads.   (After  Huntley.) 


CHAPTER  XXIII 
MEXICO 

The  oil  fields  of  Mexico1  are  on  the  Gulf  coast  in  the  States  of 
Vera  Cruz,  Tamaulipas  and  Tabasco.  The  northern  Vera  Cruz 
region  (Fig.  200),  which  includes  the  ports  of  Tampico  and  Tux- 
pam,  supplies  almost  the  entire  production. 

The  output  in  1917  was  distributed  among  the  various  fields 
as  follows:2 

Tampico-Tuxpam  zone: 

Barrels  of  42 

Panuco  River  valley  region :  Gallons 

San  Pedro  field 1  ,955 

Ebano-Chijol  field 1  ,125  ,702 

Topila  field 815  ,954 

Panuco  field .14  ,955  ,940 


Total  region  ..................  ......................   16  ,899  ,551 


V.  R.  :  The  Oil  Region  of  Northeastern  Mexico.  Econ.  Geology, 
vol.  10,  pp.  195-224,  1915;  Effect  of  Igneous  Intrusions  on  the  Accumulation 
of  Oil  in  Northeastern  Mexico.  Jour.  Geology,  vol.  20,  pp.  666-672,  1912. 

HUNTLEY,  L.  G.  :  The  Mexican  Oil  Fields.  Am.  Inst.  Min.  Eng.  Bull.  105, 
pp.  2,067-2,106,  1915. 

ARNOLD,  RALPH:  Conservation  of  Oil  and  Gas  Resources  of  the  Americas. 
Second  Pan  American  Sci.  Cong.  Proc.,  vol.  3,  pp.  217-218,  1917. 

DUMBLE,  E.  T.:  Tertiary  Deposits  of  Eastern  Mexico.  Science,  vol.  35, 
i  pp.  906-908,  1912. 

BOSE,  EMIL:  La  Fauna  de  Moluscos  del  Senoniano  de  Cardenas.  Inst. 
Geol.  Mexico  Bol.  24,  95  pp.,  18  pis.,  1906. 

VILLARELLO,  J.  D.  :  Algunas  Regiones  Petroliferas  de  Mexico.  Inst.  Geol. 
Mexico  Bol.  26,  120  pp.,  3  pis.,  1908. 

ORDONEZ,  EZEQUIEL:  Occurrence  and  Prospects  of  Oil  in  Mexico.  Eng.  and 
Min.  Jour.,  vol.  89,  p.  1,020,  May  14,  1910;  The  Oil  Fields  of  Mexico.  Am. 
Inst.  Min.  Eng.  Trans.,  vol.  50,  pp.  859-869,  1914. 

BALL,  S.  H.  :  The  Tampico  Oil  Field,  Mexico.  Eng.  and  Min.  Jour.,  vol.  91, 
pp.  958-961,  May  13,  1911. 

WHITE,  I.  C.  :  Gulf  Coast  Petroleum  Fields  of  Mexico  Between  the  Tamesi 
and  Tuxpan  Rivers.  Geol.  Soc.  America  Bull,  vol.  24,  pp.  253-274,  1913. 

2DE  GOLYER,  E.  :  The  Petroleum  Industry  of  Mexico.  Evening  Post  Oil- 
Industry  Suppl.  New  York,  Aug.  31,  1918,  p.  17. 

497 


498  GEOLOGY  OF  PETROLEUM 

Barrels  of  42 

Tuxpam  region:  Gallons 

Casiano-Tepetate  field 8  ,153  ,692 

Tanhuijo-San  Marco  field 3  ,093 

Cerro  Azul  field 9  ,171 ,478 

Potrero-Alazan  field 16  ,893  ,717 

Alamo  field 4  ,112  ,899 

Furbero  field 34  ,689 


Total  region 38  ,369  ,663 


Total  zone 55  ,269  ,214 

Tehuantepec-Tabasco  zone 23  ,556 


Total  Mexico 55  ,292  ,770 

This  output  came  principally  from  five  large  wells,1  of  which  the 
Juan  Casiano  No.  7  and  Potrero  del  Llano  No.  4,  two  famous 
gushers  drilled  in  1910,  supplied  a  large  amount.  In  all  there  were 
at  the  end  of  1917  in  Mexico  339  productive  wells,  with  a  daily 
estimated  capacity  of  1,337,213  barrels  of  oil.  Some  of  the  wells 
in  Mexico  have  unusually  long  life,  especially  for  gushers  of  such 
magnitude.  Most  of  the  oil  produced  in  Mexico  is  a  heavy  fuel 
oil,  but  recently  lighter  oil  yielding  considerable  gasoline  has' been 
found.  Salt  water  is  associated  with  the  oil,  and  at  some  places 
the  water  is  hot.  Some  of  the  large  wells  recently  have  gone  to 
salt  water. 

In  northern  Vera  Cruz  the  coastal  plain  is  about  GOjpiles  wide. 
The  country  is  comparatively  flat  and  is  forested.  .xjFis  an  area  of 
sedimentary  rocks  intruded  by  many  dikes  and  plugs  of  basic 
igneous  rocks.  Along  the  plain  the  rocks  are  nearly  flat-lying 
except  where  disturbed  locally  by  intrusions.  To  the  west,  along 
the  east  flank  of  the  Sierra  Madre  Oriental,  the  sediments  are 
closely  folded.  The  rocks  are  of  Cretaceous  and  later  age.  A 
table  of  formations  is  given  on  p.  499. 

The  principal  oil-bearing  rock  is  the  Tamasopa,  a  series  of  lime- 
stones which  make  up  the  core  of  the  Sierra  Madre  Oriental  along 
the  western  rim  of  the  coastal  plain.  These  limestones  are  3,000 
feet  thick  and  are  for  the  most  part  gray  and  massive.  This 
series  is  placed  by  some  in  the  Lower  Cretaceous  and  by  others  in 

^LARDONE,  GEORGE:  Mexico's  Petroleum  Production  in  1917.  Oil  and 
Gas  Jour.  (Tulsa,  Okla.),  vol.  16,  No.  34,  pp.  28,  32,  1918. 


MEXICO 


499 


TENTATIVE  CORRELATION  OF  THE  TERTIARY  AND  CRETACEOUS  FORMATIONS 

OF  NORTHEASTERN  MEXICO 
Tertiary:  (After  Garfias) 

Pliocene: 

Miocene: 

Tuxpan . 

Later  Tertiary  clays,  limestones, 

Oligocene:  t     and  sands,  about  700  feet. 
San    Fernando    (yellow    clays,    lime- 
stones, and  sands) 

Eocene : 

Alazan  shales 

Mendez  shales  (in  part) 

Cretaceous'  Cretaceous-Eocene  shales,  about 

Upper:    '  3,000  feet. 

Papagallos  shales 

Mendez  shales  (in  part) 

San  Felipe  limestones  and  shales 1  Upper  Cretaceous  limestones  and 

Cardenas J     shales,  about  500  feet. 

Lower: 
Middle: 

Tamasopa  limestone Lower     Cretaceous     limestones, 

about  3,000  feet. 
Lower: 

El  Abra  limestone 

the  Upper  Cretaceous.  It  is  named  after  the  Tamasopa  Canyon, 
where  a  section  is  exposed.  The  limestones  vary  in  different 
localities,  are  fossiliferous,  and  have  a  slight  petroliferous  odor. 
The  oil  occurs  in  solution  cavities  and  in  other  openings  in  the 
limestone  and  is  associated  with  salt  water. 

Overlying  the  Lower  Cretaceous  limestones  is  the  San  Felipe1 
formation,  a  series  of  interbedded  limestones  and  shales  in  which 
the  shale  increases  toward  the  top.  The  San  Felipe  limestones 
and  shales  form  some  of  the  principal  sources  of  oil  in  the  region. 
These  rocks  constitute  ideal  reservoirs,  particularly  where  they  are 
fractured  or  folded,  as  near  intrusions.  The  oil  occurs  to  some 
extent  in  the  porous  limestones,  but  more  generally,  perhaps,  in 
interstices  in  the  shales.  Wells  that  are  apparently  finished  in  the 

Others  place  Hicsc  rocks  higher  in  the  geologic  column  than  is  shown  in  the 
table  by  G  Aim  AS. 


500 


GEOLOGY  OF  PETROLEUM 


San  Felipe  draw  their  major  oil  supply  from  the  Tamasopa  lime- 
stone through  fissures.  According  to  Arnold,1  the  Potrero  No.  4 
was  finished  in  the  San  Felipe,  but  a  great  number  of  blocks  of 
Tamasopa  rocks  were  blown  out  when  the  well  came  in. 


3  Quaternary  and  recent 

^  Upper  Tertiary 

§§|  Mendez  marh  (Eocene) 

H  San  Felipe  (Voiles)  beds. 
Jamoisopa  lime(Lower 
Igneous  intrusions 
Igneous  dikes 


FIG.  201. — Generalized  sketch  map  of  the  oil  fields  in  the  Northern  Vera 
Cruz  region,  Mexico,  showing  areal  geology,  location  of  main  basaltic  intru- 
sions and  strike  of  the  main  dikes  in  the  central  district.  (After  Jeffreys.} 


Unconf ormably  above  the  San  Felipe  beds  is  a  series  of  uniform 
marls,  and  clays,  the  Mendez,  2,000  to  3,000  feet  thick.  This 
formation  is  impervious  and  forms  the  cap  rock  of  the  main 
oil  reservoirs;  it  is  also  a  reservoir  rock  where  conditions  are 
favorable.  Some  of  the  wells  derive  oil  from  the  Mendez,  partic- 


1  ARNOLD,  RALPH:  Conservation  of  Oil  and  Gas  Resources  of  the  Americas. 
Second  Pan  American  Sci.  Cong.  Proc.,  vol.  3,  pp.  217-218,  1917. 


MEXICO 


501 


FIG.  202. — Hypothetical  geological  section  through  Panuco  field,   Mexico, 

(After  Huntley.} 


502 


GEOLOGY  OF  PETROLEUM 


FIG.  203.  —  Map  of  a  portion  of  Vera  Cruz  oil  field.  Shows  the  relations  of 
the  principle  igneous  intrusions  to  oil  seeps  and  gushers  that  have  been  drilled 
at  Dos  Bocas,  Juan  Casiano  and  Los  Naranjos.  (After  Huntley.) 

ularly  its  lower  members,  without  reaching  the  Upper  Cretaceous 
limestones  and  shales.1 


,  V.  R.  :  The  Effect  of  Igneous  Intrusions  on  the  Accumulation  of 
Oil  in  Northeastern  Mexico.     Jour.  Geology,  vol.  20,  pp.  666-672,  1912. 


MEXICO 


503 


l*n  conformably  overlying  the  marls  is  a  succession  of  fossilifrr- 
01  is  grayish  limestones  and  shales  with  minor  amounts  of  con- 
glomerate and  sand  having  an  average  thickness  of  about  700  feet. 
These  beds  arc  of  little  importance  in  connection  with  the  com- 
mercial accumulation  of  oil  in  this  region,  and  they  form  a  rather 
porous  covering  over  the  impervious  Eocene-Cretaceous  shales. 
Under  favorable  conditions,  however,  where  the  shales  have  been 
fractured,  allowing  the  oil  to  migrate  to  the  overlying  porous  beds, 
accumulations  of  oil  have  been  formed. 

Dikes,  sills,  and  stocks  of  basaltic  rock  intrude  the  sedimentary 
beds  (Figs.  201  and  202).  Most  of  the  surface  indications  of  oil  are 
closely  associated  with  the  basalts,  and  hundreds  of  them  occur 
throughout  the  plain.  Among  the  localities  where  oil  seeps  are 
abundant  are  Panuco,  Dos  Bocas,  Casiano,  Tres  Hermanos,  Ojo 
do  Brea,  Chapopotillo,  Monte  Grande,  and  many  others. 


FIG.  204. — Diagrammatic   geological   section   across   southern   part   of   area 
shown  in  Fig.  203.   (After  Huntley.) 

The  strata  dip  eastward  from  the  Sierra  Madre  Oriental  at  low 
angles.  This  low  monoclinal  structure  has  been  modified  to  the 
south  by  volcanic  intrusions,  which,  trending  in  a  southeasterly 
direction,  have  in  this  region  upturned  the  monocline  slightly  to 
he  northeast.  Huntley1  states  that  all  the  large  wells  are  located 
where  there  is  anticlinal  or  dome  structure  and  pronounced  frac- 
turing of  the  rock.  The  fractures  are  usually  accompanied  by 
basaltic  intrusions  and  seeps  of  asphalt  and  gas1  (Figs.  203 
and  204). 

According  to  Garfias,  three  anticlines  running  approximately 

JHuNTLEY,  L.  G.:  Mexican  Oil  Fields.  Am.  Inst.  Min.  Eng.  Trans.,  vol.  52, 
pp.  281-322,  1915. 


504  GEOLOGY  OF  PETROLEUM 

north  and  south  have  been  traced — one  near  Ebano,  another 
between  Mendez  and  Chila,  and  the  third  between  Tamos  and 
Ochoa.  In  the  area  between  Panuco  and  Topila  there  are  at  least 
two  such  folds,  and  a  well-defined  line  of  weakness  marked  at  the 
surface  by  oil  seeps  extends  from  Otontopec  to  Tantima  and  thence 
to  Dos  Bocas.  Faults  are  numerous  but  are  difficult  to  trace 
owing  to  the  surface  cover. 

Arnold  states  that  the  San  Diego,  Casiano,  Naranjos,  Tierra 
Amarilla,  Potrero,  and  Alamo  fields  are  clearly  anticlinal.     The 


FIG.  205.— Sketch  map  of  Furbero  oil  field,  Mexico.  Numbers  refer  to  wells 
shown  on  Fig.  206.  (After  De  Golyer.} 


structure  of  the  Topila,  Panuco,  Chijol,  and  Chila  Salinas  fields 
is  not  clearly  marked,  but  it  is  probable  that  they  are  the  result  of 
the  filling  of  porous  beds  in  the  San  Felipe  formation  through 
fissures  that  extend  to  the  Tamasopa. 

In  the  Ebano  field,  which  was  one  of  the  first  drilled,  the  out- 
cropping rocks  are  the  upper  Tertiary  and  the  Mendez  marls. 
The  sedimentary  rocks  dip  toward  an  igneous  plug  near  the  plug 


MEXICO 


505 


but  dip  away  from  it  a  short  distance  away,  thus  showing  anti- 
clinal ring  and  funnel  structure.  Evidently  the  plug  thrust  the 
rocks  up;  then  on  cooling  and  contracting  it  dragged  them  down 


shale 
Igneous  rock    £ 


FIG.  206. — Geological  cross  section  of  the  Furbero  oil  field.  Position  of  wells 
shown  on  Fig.  205.   (After  De  Golyer.) 

around  the  edges.     This  phenomenon,  according  to  Garfias,  is 
not  uncommon  in  Mexico.     (See  p.  136.) 


506  GEOLOGY  OF  PETROLEUM 

The  Furbero  district1  lies  in  the  Gulf  coastal  plain  of  Mexico, 
between  Tampico  and  Vera  Cruz,  and  is  the  southernmost  district 
developed  in  the  Tampico-Tuxpam  region.  The  country  is  for 
the  most  part  a  flat-lying  tropical  jungle  with  comparatively  few 
outcrops.  Oil  seeps  have  long  been  recognized  in  the  region 
(Fig.  205).  The  surface  rock  over  most  of  the  region  is  the  Men- 
dez  shale.  Below  this  the  San  Felipe  and  Tamasopa  are  believed 
to  be  present.  The  igneous  rocks  in  the  region  consist  of  basalts, 
dolerites,  basalt-gabbros,  and  various  products  of  volcanic  activity, 
such  as  volcanic  sands  and  ash.  A  ridge  of  indurated  fractured 
shale  is  found  within  the  area  of  the  Mendez  shale.  Underground 
exploration  has  shown  that  this  is  the  top  of  a  pipelike  body  of 
hydrothermally  altered  and  indurated  rock,  lying  above  a  thick 
dome  of  gabbro  or  dolerite  which  is  a  part  of  a  great  sill  (Fig.  206). 
The  sedimentary  rocks  bend  upward,  forming  an  anticline.  Both 
the  igneous  rock  and  the  indurated  part  of  the  Mendez  shale  con- 
tain openings  and  form  the  reservoir  for  the  oil.  In  several  wells 
salt  water  was  encountered  below  the  oil.  The  crest  of  the  lacco- 
lith or  dome  lies  altogether  outside  the  most  productive  area, 
though  some  oil  has  been  encountered  in  every  well  drilled  to  a 
depth  at  which  it  might  reasonably  be  expected.  DeGolyer 
believes  that  the  porosity  of  the  beds  rather  than  the  anticlinal 
fold  was  the  controlling  feature.  A  sample  of  the  igneous  rock, 
according  to  DeGolyer,  showed  a  porosity  of  6  per  cent.  He 
believes  that  the  oil  was  originally  in  the  Tamasopa  (Cretaceous) 
beds.  The  Mendez  shale  is  generally  impervious  and  not  pro- 
ductive, but  in  the  Furbero  field  part  of  it  has  been  thoroughly 
baked  and  metamorphosed  into  a  hard  brown  to  black  porous  shale 
and  forms,  together  with  the  crystalline  igneous  rock,  the  oil 
reservoir  of  the  field.  Apparently  much  of  the  metamorphism 
has  been  due  to  the  action  of  ascending  thermal  waters  associated 
with  the  igneous  rock  after  its  intrusion.  The  thickness  of  this 
formation  at  Furbero  is  approximately  4,000  feet.  Overlying 
the  Mendez  shale  is  a  thick  series  of  sandstones,  shales,  impure 
fossiliferous  limestones,  and  conglomerates  of  Oligocene  age. 

'DEGOLYER,  E.  L. :  The  Furbero  Oil  Field,  Mexico.  Am.  Inst.  Min.  Eng. 
Bull.  105,  pp.  1,899-1,911,  1915. 


CHAPTER  XXIV 
EUROPE,  EXCEPT  RUSSIA. 
GREAT  BRITAIN 

Oil  seeps,  bitumens,  and  pitch  are  found  at  many  places  in 
Great  Britain,  but  there  was  no  production  of  oil  until  1919,  when 
a  flowing  well  was  brought  in  at  Hardstoft,  Derbyshire.  A 
variety  of  bitumen,  known  as  "mineral  india  rubber"  on  account  of 
its  elastic  properties,  was  found  at  an  early  date  in  the  Odin  mine, 
near  Castleton,  Derbyshire,  and  was  called  elaterite1  by  Haus- 
mann.  Bituminous  deposits  are  known  in  Shropshire,  Lancashire, 
and  other  counties. 

Natural  gas  has  been  reported  from  Wigan,  England,  also  from 
Scotland  and  Wales.  During  the  construction  of  the  Thames 
Tunnel  inflammable  gas  was  encountered  in  such  quantities  that 
it  exploded  on  coming  into  contact  with  the  lights  used  by  the 
workmen.  The  principal  source  of  gas  in  England  is  at  Heath- 
field,  Sussex.  There  it  was  first  discovered  in  1893  at  a  depth  of 
228  feet  in  a  bore-hole  sunk  for  water  close  to  the  railway  station. 
No  water  was  found,  and  as  the  gas  was  considered  dangerous,  the 
well  was  sealed.  In  1896  another  boring  for  water  was  made  near 
by,  and  at  a  depth  of  312  feet  gas  was  found  in  considerable  quan- 
tities. The  boring  was  carried  to  377  feet  and  abandoned,  as  no 
water  was  found.  The  well  was  capped,  and  the  gas  was  utilized 
for  illuminating  and  heating.  About  1,000  cubic  feet  was  used 
daily  for  a  period  begun  in  1896.  The  gas  is  said  to  be  richer  in 
hydrocarbons  than  American  natural  gas,  and  to  burn  with  a 
more  brilliant  flame.  Other  wells  have  been  bored  in  the  neighbor- 
hood, in  which  gas  is  said  to  have  been  met  at  a  depth  of  400  feet 
with  a  pressure  of  200  pounds  to  the  square  inch,  and  the  aggregate 
output  for  1904  is  officially  reported  to  have  been  774,800  cubic 
feet.  In  1909  236,800  cubic  feet  was  obtained.2 

Practically  all  the  oil  produced  in  Great  Britain  to  1919  was 
obtained  from  the  distillation  of  the  oil  shales  of  Scotland. 

REDWOOD,  BOVERTON:  A  Treatise  on  Petroleum,  vol.  1,  p.  34,  1913. 

REDWOOD,  BOVERTON:  Op.  tit.,  p.  36. 

507 


508  GEOLOGY  OF  PETROLEUM 

The  dominating  feature  of  north  England  is  the  anticline  of  the 
Pennine  Hills,  which  extends  from  Scotland  southward  to  Derby- 
shire. Along  the  axis  of  this  anticline,  in  the  center  of  England, 
the  Mountain  limestone  (Mississippian)  is  exposed.  It  contains 
numerous  seeps  of  petroleum.  The  upper  100  to  150  feet  of  this 
limestone  is  dolomitic.  Overlying  the  Mountain  limestone  are 
the  Yoredale  shales  and  sandstones,  which  in  the  area  to  the  east 
of  the  axis  have  a  thickness  of  400  to  700  feet,  and  in  the  area  to 
the  west  2,000  to  2,500  feet.  Above  the  Yoredale  shales  are  the 
Millstone  grits,  a  series  of  shales  and  porous  sandstones  with  a 
total  thickness  on  the  east  of  700  to  900  feet  and  on  the  west  of 
about  300  feet;  these  in  turn  are  succeeded  by  the  productive  coal 
measures.  On  each  side  of  the  main  Pennine  fold,  subsidiary  folds 
produce  a  series  of  local  domes,  anticlines,  and  terraces  in  the 
regions  where  the  limestone  is  overlain  by  the  Yoredale  and  suc- 
ceeding rocks.1  There  is  considerable  faulting,  but  although  the 
oil  produced  in  the  limestone  has  a  paraffin  base,  it  oxidizes, 
according  to  Veatch,  more  rapidly  than  an  asphaltic  oil.  There 
are  no  surface  exudations  of  oil  on  either  side  of  the  main  limestone 
mass,  but  for  the  last  century  the  coal  mines  on  both  sides  have 
encountered  flows  of  oil  on  fault  planes. 

The  discovery  well  is  on  a  faulted  dome  at  Hardstoft,  Derby- 
shire. It  started  in  the  coal  measures,  found  wax  in  drilling 
through  a  fault,  and  a  commercial  supply  of  gas  in  the  Millstone 
grits,  which  was  muddied  off.  Oil  was  found  in  the  top  of  the 
limestone  at  a  depth  of  3,078  feet.  This  well  flowed  at  the  rate 
of  12  barrels  a  day  from  June  1919,  to  the  end  of  the  year,  and  is 
estimated  by  Veatch  to  have  a  pumping  capacity  in  excess  of  50 
barrels. 

The  oil  from  the  Hardstoft  well  has  the  following  characteristics  : 
Specific  gravity,  0.823;  sulphur,  0.26  per  cent;  gasoline,  7.5  per 
cent;  kerosene,  39.0  per  cent;  wax,  6.0  per  cent;  gas  oil,  20.0  per 
cent;  lubricating  oil,  30.0  per  cent.  The  oil  is  particularly  rich 
in  very  high-grade  lubricants. 

The  area  in  central  England  that  has  possibilities  of  producing 
petroleum  is,  according  to  Veatch,  between  20,000  and  30,000 
square  miles. 


,  A.  C.:  Petroleum  Resources  of  Great  Britain,  pamphlet  issued  by 
Am.  Inst.  Min.  Eng.,  January,  1920.  Mining  and  Metallurgy,  No.  157,  sec.  3, 
pp.  1-4,  1920. 


EUROPE,  EXCEPT  RUSSIA  509 

GENERALIZED  GEOLOGIC  SECTION  OF  PENNINE  REGION,  ENGLAND* 

Coal  measures: 

Red  and  gray  sandstones,  clays,  and  at  some  places  breccias,  with  occasional 

seams  and  streaks  of  coal. 
Middle  or  chief  coal-bearing  series  of  yellow  sandstones,  clays,  and  shales, 

with  numerous  workable  coals. 
Canister  beds,  flagstones,  shales,  and  thin  coals,  with  hard,  siliceous  (gan- 

ister)  pavements. 

Millstone  grit: 

Grits,  flagstones,  and  shales  with  thin  seams  of  coal. 
Carboniferous  limestone  series: 

Yoredale  group  of  shales  and  grits,  passing  down  into  dark  shales  and 
limestones. 

Thick  (Scaur  or  Main)  limestone  in  south  and  center  of  England  and  Ire- 
land, passing  northward  into  sandstones,  shales  and  coals  (abundant 
corals,  polyzoans,  brachiopods,  lamellibranchs,  etc.) 

Lower  limestone  shale  of  south  and  center  of  England  (marine  fossils  like 
those  of  overlying  limestone).  The  Calciferous  sandstone  group  of  Scot- 
land (marine,  estuarine,  and  terrestrial  organisms),  represents  the  lower 
limestone  shale  ard  lower  part  of  the  English  Mountain  limestone,  and 
graduates  downward  insensibly  into  the  upper  Old  Red  sandstone. 

aGEiKiE,  ARCHIBALD:  Text-book  of  Geology.    P.  737,  London,  1882. 


FIG.  207. — Geological  cross  section  through  the  Schwabweiler  oil  field,  Alsace. 
The  dark  beds  are  petroliferous,  (After  Andreae.) 

FRANCE 

The  oil  fields  of  Alsace1  were  among  the  earliest  exploited.     The 

TVoN  WERVEKE,  L. :  Vorkommen,  Gewinnung  und  Entstehung  des  Erdols 

in  Unter-Elsass.     Zeitschr.  prakt.  Geologic,  vol.   13,  pp.  97-114,  1895;  Die 

Entstehung  der  Unterelsaessischen  Erdoellager  Erlaeutert  an  der  Schichten- 

folge   im   Oligocaen.      Philomat.    Gesell.    Elsass-Lothringen,    Band   4,    pp. 

697-721, 1913;  (review  by  W.  H.  BUCHER,  Econ.  Geology,  vol.  12,  p.  203,  1917). 

ANDREAE,  A.:  Notiz  Ueber  das  Tertiar  im  Elsass.     Neues  Jahrb.,  1882, 

Band  2,  pp.  287-294. 


510 


GEOLOGY  OF  PETROLEUM 


Pechelbronn  field  has  been  worked  on  a  commercial  scale  since 
1742.  In  the  early  days  shafts  were  sunk  to  depths  of  300  feet. 
In  1880  drilling  methods  were  introduced,  and  since  that  date  the 
fields  have  yielded  a  small  but  steady  supply.  Nearly  1,800  wells 
have  been  drilled,  reaching  depths  as  great  as  1,300  feet.  The  oil 
comes  from  the  Tertiary  strata;  the  Mesozoic  rocks  have  yielded 
only  negligible  quantities.  The  oil  ranges  from  0.880  to  0.900 
in  specific  gravity.  Figs.  207  and  208  are  cross-sections  of  the 
fields. 

The  youngest  Mesozoic  rocks  of  the  region  are  Jurassic.  Upon 
them  rest  unconformably  Eocene  fresh- water  limestones  and 
brown  coal.  These  are  overlain  by  upper  Eocene  nonfossiliferous 
conglomerates,  upon  which  lie  the  extensive  thick  marl  beds  of 


FIG.  208. — Longitudinal  section  through  the  upper  oil  sands  of  Pechelbronn, 
Alsace.  The  dark  beds  are  petroliferous.  (After  Andreae.) 


the  lower  Oligocene,  the  most  productive  oil-bearing  formation  of 
the  region.  The  bulk  of  this  formation  consists  of  gray,  gray- 
green,  brown,  or  red  marl,  interstratified  with  sands  and  sand- 
stones and  subordinate  limestones,  with  lenses  of  anhydrite, 
gypsum,  and  pyrite.  The  sands  are  lens-shaped,  many  of  them 
curved  and  branching.  They  rarely  exceed  12  feet  in  thickness 
and  have  a  maximum  length  of  2,500  feet  and  a  width  of  100  to  200 
feet.  The  oil  is  confined  almost  exclusively  to  these  sands.  Near 
Schwabweiler  the  marl  beds  pass  gradually  into  the  middle  Oligo- 
cene sandstones;  at  some  other  places  they  are  overlain  by  lime- 
stone, some  of  which  contains  as  much  as  18  per  cent  of  bitumen. 
The  individual  beds  are  from  4  to  8  feet  thick.  They  alternate 
with  coal  seams  20  inches  or  less  thick. 


EUROPE,  EXCEPT  RUSSIA  511 

The  section  of  the  petroliferous  series,  as  worked  out  from  cores 
of  deep  bore  holes  by  Von  Werveke,  is  as  follows: 

Metere 
Gray  marls 375 

Alternating  beds  of  marls  (with  numerous  sun-cracked  layers).  Upper 
part,  variegated  marine  marls  containing  anhydrite  alternating  with 
gray,  green,  red,  and  brown  fresh-water  marls,  containing  sandstone 
layers  with  Limnaeus  and  Planorbis.  Lower  part,  variegated  highly 
fossiliferous  marine  marls,  with  Mytilus,  Pecten,  Mactra,  Thracia, 
Hydrobia,  Euchilus,  etc.,  alternating  with  colored  fresh-water  marls, 
with  Limnaeus,  containing  sandstone  layers,  locally  rich  in  bitumen  .  .  475 

Red  marls,  locally  green,  and  sandstone,  with  Limnaeus,  containing 
bitumen _ 100 

Gray  and  green  fresh-water  marls,  red  or  brown  in  lower  part,  and 
numerous  sandstone  layers,  with  sun  cracks  and  Limnaeus 150 

Gray  and  black  marine  marls  with  anhydrite  (no  sandstone) 80 


Locally,  where  fresh-water  and  marine  strata  alternate,  oil  and 
bitumen  occur  in  varying  amounts.  The  oil  field  is  in  the  great  fault 
trough  of  the  upper  Rhine  Valley.  All  the  strata  mentioned  above 
were  involved  in  the  post-Oligocene  movements  which  created  the 
great  trough.  Small  faults  are  closely  spaced.  The  direction  of 
the  major  faults  is  north-northeast.  The  beds  dip  toward  the  Rhine. 
The  oil  fields  lie  in  the  disturbed  area  on  the  downthrown  side. 

The  structural  features  that  influence  accumulation  are  the 
faults  and  the  sandy  lenses  in  the  marl  beds,  rather  than  folds. 
At  Pechelbronn  a  number  of  oil  sands  are  encountered  at  depths  of 
250  to  270,  350  to  450,  550  to  600,  750,  and  1,000  feet. 

The  yields  of  the  different  beds  admit  of  no  conclusion  as  to 
which  are  the  most  prolific.  In  some  wells  only  gas  and  water  are 
struck.  Near  Schwabweiler  a  number  of  successful  wells  were 
sunk.  Here  the  oil  sands  are  of  great  areal  extent  and  are  prob- 
ably connected.  The  dip  of  the  beds  is  comparatively  steep,  and 
minor  faulting  is  common.  South  of  the  Zorn  River  oil  was 
encountered  in  younger  beds  (middle  Oligocene).  Whether  or 
not  it  entered  these  beds  from  the  lower  main  oil  zone  is  uncertain. 


512  GEOLOGY  OF  PETROLEUM 

PETROLEUM  PRODUCED  IN  THE  GERMAN  EMPIRE,  1908-1917 


Year 

Alsace- 
Lorraine 

Prussia 

Total 

1908            

Metric  Tons 

"28  ,898 
°29  ,726 

Metric  Tons 

113  ,002 
113,518 

Metric  Tons 

141  ,900 
143  ,244 
145  ,168 
142  ,992 
144  ,961 
140  ,000 
140  ,000 
140  ,000 
140  ,000 
140  ,000 

Barrels 
(42  Gallons) 

,009  ,278 
,018  ,837 
,032  ,522 
,017  ,045 
,031  ,050 
995  ,764 
C95  ,764 
995  ,764 
995  ,764 
995  ,764 

1909 

1910 

1911                  

1912  

1913&         

1914b 

19156 

19166 

19176 

alnclude9  Bavaria. 

Estimated. 

1  metric  ton,  crude=7.1126  barrels. 

As  pointed  out  by  Von  Werveke,  and  as  noted  above,  the  oil- 
bearing  series  is  in  part  marine  and  in  part  nonmarine.  During 
the  period  of  its  deposition  conditions  changed  from  salt  water  to 
fresh  water,  terrestrial,  and  arid.  In  the  150  meters  of  exclusively 
fresh-water  strata  in  the  lower  part  of  the  section  oil  is  absent, 
although  these  beds  contain  numerous  porous  sandstones.  At 
the  base  of  the  fresh-water  strata,  where  they  alternate  with 
marine  sediments, .  some  oil  occurs.  Where  anhydrite  is  present 
oil  is  absent.  The  arid  conditions  that  permit  anhydrite  to  form 
are  evidently  unfavorable  to  life  and  to  the  development  of  mate- 
rial from  which  oil  may  be  derived.  The  greatest  yield  of  oil  is 
obtained  from  strata  composed  of  fresh-water  beds  alternating 
with  highly  fossiliferous  marine  beds.  Von  Werveke  concludes 
that  the  oil  originated  essentially  where  it  is  found,  and  that  it  was 
derived  from  animal  remains  along  a  shore  line  where  conditions 
repeatedly  changed  from  marine  to  nonmarine.  As  the  Jurassic 
black  shales  below  the  oil  strata  are  not  much  altered  he  concludes 
that  distillation  has  played  a  small  part  in  the  formation  of  the  oil, 
which  he  attributes  to  polymerization.  He  cites  the  high  heat 
gradient  of  the  district  and  connects  it  with  the  exothermic  process 
of  polymerization. 


EUROPE,  EXCEPT  RUSSIA  513 

GERMANY 

The  north  German  or  Prussian  oil  field  is  a  belt  lying  between 
the  Weser  and  Elbe  rivers  north  of  the  Harz  Mountains,  including 
the  Wietze,  Steinforde,  Oelheim,  and  other  pools  of  Hannover. 
The  production  of  petroleum  comes  chiefly  from  limestones  and 
sandstones  of  the  Upper  Jurassic  or  from  transitional  beds  between 
the  Jurassic  and  Cretaceous. 

In  1897,  according  to  Redwood,1  80  wells  yielded  an  average  of 
20  barrels  a  day.  In  1899  wells  were  sunk  to  depths  of  140  to  200 
meters,  and  a  more  abundant  supply  was  reached,  as  much  as  400 
barrels  a  day  being  obtained  from  a  single  well.  The  oil  was  of  a 
dark  reddish-brown  color,  with  a  specific  gravity  of  0.930,  and  was 
rich  in  lubricants.  In  1901  wells  drilled  deeper  found  an  oil-bear- 
ing stratum  containing  green  oil,  with  a  specific  gravity  of  0.890. 

Oelheim2  or  Eddesse  is  the  chief  center  of  the  production  of  oil, 
which  fills  crevices  in  the  Cretaceous  clay,  saturates  the  Wealden 
sandstones,  and  occurs  scantily  in  the  Lower  Jurassic,  upon  which 
these  beds  rest.  Across  the  upturned  edges  of  these  beds  lies  a 
sandstone  of  upper  Tertiary  age,  charged  with  tar  and  known  as 
the  Tarpits  rock.  About  15  kilometers  to  the  northwest  of  Oel- 
heim, at  Haningsen  and  Obbershagen,  the  lignitiferous  Tertiary 
deposits  are  impregnated  with  tar,  and  oil  occurs  in  the  subjacent 
Triassic.  The  same  conditions  exist  at  Steinforde,  Wietze,  Horn- 
bostel,  Winsen,  and  Eickeloh,  northwestward  of  Celle. 

An  asphalt  deposit  occurs  west  of  Limmer, 3  on  the  highway  from 
that  village  to  Harenberg.  The  asphalt-bearing  beds  are  Upper 
Jurassic  and  lie  between  the  Pteroceras  beds  and  the  Eimbeck- 
hauser  Plattenkalke  (thin  beds  of  limestone).  The  beds  in  the 
southern  part  of  the  deposit  strike  northeast  and  dip  24°  SE. 
(See  Figs.  209  and  210.)  A  fault  nearly  parallel  in  strike  in  the 
southern  part  but  diverging  toward  the  northeast,  with  the  fault 
plane  dipping  45°  NW.,  cuts  off  the  asphalt-bearing  beds,  and  not 
very  far  below  the  surface  the  formation  ends  in  a  wedge.  Two 
minor  faults  also  are  indicated  on  the  accompanying  cross-section 
(Fig.  210).  The  barren  footwall  belongs  to  another  formation, 
the  Hils  clay.  All  the  asphalt  beds  have  a  strong  bituminous  odor 

'REDWOOD,  BOVERTON.  A  Treatise  on  Petroleum,  vol.  1,  p.  29,  1913. 
2Idem,  p.  146. 

HOFFMANN,  F.  A.:  Asphalt-Vorkommen  von  Limmer  bei  Hannover  und 
von  Vorwohle  am  Hils.  Zeitschr.  prakt.  Geologie,  1875,  pp.  370-379. 


514 


GEOLOGY  OF  PETROLEUM 


and  upon  fracturing  become  quickly  covered  with  brown  drops  of 
bitumen.     Weathered  pieces  are  white.     The  bitumen  content 

averages  12  to  14  per  cent,  and  some 
/"'"* l  \  beds  carry  as  high  as   18   per  cent. 

The  asphalt  rock  is  extracted  chiefly 
by  open-pit  mining. 

Asphaltic  beds  are  found  at  Vor- 
wohle  on  the  southwest  slope  of  Hils 
Mountain.  They  belong  to  the  Upper 
Jurassic.  The  only  bed  of  economic 
importance  is  an  asphaltic  limestone 
about  22  feet  thick.  It  contains 
about  6  per  cent  of  bitumen  which  is 
concentrated  in  little  oolitic  grains. 
A  faint  odor  of  bitumen  is  noticeable 
in  the  rock.  Overlying  the  asphalt 
limestone  are  thinly  bedded  calcareous 
and  marly  strata.  The  asphaltic 
rock  is  quarried  and  used  for  paving. 


FIG.  209. — Plan  of  asphalt 
deposit  near  Limmer,  Han- 
over, Germany.  For  section 
along  line  AB,  see  Fig.  210. 
(After  Hoffman.) 


ITALY 


The  oil  fields  of  Italy  include  the  Emilia  field,  the  Chieti  field, 
and  the  Liris  Valley  fields  between  Rome  and  Naples  (Fig.  211). 

The  Emilia  and  Chieti  fields  are  on  the  northeast  slope  of  the 
Apennine  Range.  This  range  is  made  up  of  a  central  core  con- 
sisting chiefly  of  Cretaceous,  Eocene,  and  Miocene  rocks,  which 
dip  northeast  toward  the  River  Po  and  the  Adriatic  and  which  ai 
covered  at  places  by  Pliocene  sediments.1  The  sediments  are 
nearly  related  to  the  Flysch  of  Galicia.  The  Oligocene  in  general 
is  lacking. 


FIG.  210.  —  Section  of  asphalt  deposit  near  Limmer,  Hanover,  Germany.  The 
position  of  the  section  is  shown  on  Fig.  209. 


,  GEORG  :  Das  Asphaltkalkgebiet  des  Pescaratales  am  Nordabhange 
Majella  (Abruzzen).     Zeitschr.  prakt.  Geologic,  vol.  20,  pp.  169-196,  1912. 


EUROPE,  EXCEPT  RUSSIA 


515 


The  Emilia  area  occupies  parts  also  of  the  provinces  of  Piacenza, 
Parma,  Modena  and  Bologna,  in  northern  Italy.  This  area  has 
yielded  oil  in  commercial  quantities  from  Eocene,  Miocene,  and 
Pliocene  rocks,  which  are  thrown  into  folds.  The  structure  is 
complicated  and.  according  to  Redwood1  it  is  uncertain  at  some 
places  what  strata  yield  the  oil.  Near  Piacenza  oil  was  obtained 
by  piercing  the  horizontal  beds  of  gypsum  and  clay  and  drawing 
off  the  water  and  oil  that  collected.  At  Montechino  gas  issued 
from  calcareous  rocks  associated  with  beds  of  bluish  clay  of  the 
Subapennine  forma- 
tion. On  the  Neviano 
de  Rossi  property, 
near  the  Taro  River, 
shallow  wells  have 
penetrated  a  bluish 
clay,  interstratified 
with  beds  of  sandy 
rock  and  thin  beds 
of  sandstone.  In 
another  well  at  Nevi- 
ano oil  was  found  at 
a  depth  of  60  meters. 
No  sandstone  was 
encountered  in  drill- 
ing this  well  to  a, 
depth  of  110  meters, 
but  the  clay  was  in- 
terstratified with 
bands  of  sand  at  a 
depth  of  60  meters 
and  was  sandy  at  a 
greater  depth. 

At  Rivanozzana,  Pavia,  artesian  wells  have  been  drilled  to  a 
depth  of  180  meters,  and  from  some  of  them  salt  water  and  petro- 
leum were  ejected.  Other  wells  in  the  same  region  yield  oil,  gas, 
and  salt  water  from  soft  sandy  beds. 2 


FIG.  211. — Outline  map  of  Italy,  showing 
position  of  oil  fields. 


REDWOOD,  BOVERTON:  A  Treatise  on  Petroleum,  vol.  1,  p.  131, 1913. 
2CLAPP,  F.  G. :  Petroleum  and  Natural  Gas  Resources  of  Canada,  vol.  1, 
p.  10,  1914. 


516  GEOLOGY  OF  PETROLEUM 

GEOLOGIC  SECTION  IN  THE  PROVINCE  OF  CHIETI,  ITALY  ° 


German 
Classification 

French 
Classification 

Strata  in  Region  of 
Asphalt  Deposit,  Chieti 

Pliocene. 

Levantinische 
Stufe. 
Pontische  Stufe. 

Upper. 

Sarmatische  Stufe. 

Sarmatien. 

Clay,  conglomerate,  gypsum. 

£ 
|  Middle. 

§ 

II.  Mediterran- 
stufe. 
Schlier. 

Tortonien. 
Helvetien. 

Marl,  lithographic  limestone, 
asphalt. 
Limestone,  asphalt,  Bryoyoa. 

Lower. 

I.    Mediterran- 
stufe. 

Burdigalien. 

Lower  marl. 

Oligocene. 

Ludien. 
Tongrien. 
Aquitanien. 

Absent. 

Eocene. 

Bartonien. 
Lutetien. 
Ypresien. 
Landenien. 

Nummulitic  limestone. 

aTHiEL,  GEORQ:  Op.  cit.,  pp.  179,  182. 


Scale  in  thousands  offset 


FIG.  212. — Geologic  section  at  Majella,  Abruzzo,  Italy,  showing  region 
bearing  asphaltic  limestone.  1,  Nummulitic  limestone;  2,  older  marl;  3, 
Bryozoa  limestone;  4,  younger  marl;  5,  lithographic  limestone;  6,  does;  7, 
asphalt.  (After  Thiel.) 

Asphaltic  rocks  are  exploited  in  the  province  of  Chieti.  In  the 
Majella  region  the  asphaltic  deposits  are  associated  with  faults.1 
(Fig.  212). 

,  GEORG:  Op.  cit.,  p.  173. 


EUROPE,  EXCEPT  RUSSIA 
SICILY 


517 


The  Tertiary  beds  of  Sicily  are  petroliferous  at  several  places, 
and  the  oil  has  been  used  for  illuminating  for  many  centuries,  but 
no  extensive  industry  has  been  developed.  The  most  valuable 
deposits  both  of  oil  and  asphalt  lie  in  the  region  of  Ragusa,  Modica, 
and  the  Val  di  Noto.  Asphalt  beds  are  found  also  near  Leonporte. 
The  Cretaceous  limestones  of  the  Ragusa  region  are  bituminous, 
as  well  as  the  Miocene.  Some  of  the  vesicles  of  the  basaltic  lava 
of  Etna  are  filled  with  petroleum,  others  with  crystalline  paraffin, 
taken  up  by  the  molten  rock  in  its  passage  through  and  partial 
absorption  of  the  Tertiary  (or  lower)  carbonaceous  strata.1 


t£g 


FIG.  213. — Sketch  map  showing  structural  axes  in  parts  of  Europe  and  Asia 
(Based  on  map  by  Suess.) 


GALICIA 

General  Features. — The  Carpathian  Mountains  constitute  a 
long  S-shaped  uplift,  anticlinal  in  structure,  formed  at  a  late 
geologic  period.  This  axis,  according  to  Suess  (Fig.  213),  prob- 
ably extends  across  the  Black  Sea  to  the  region  of  Taman  and 
Kerch  and  in  Russia  becomes  the  Caucasus  Range,  at  the  end  of 
which  lies  the  well-known  Baku  field.  The  principal  oil  fields  of 
Galicia,  Rumania,  and  Russia  are  on  minor  folds  that  are  con- 
nected generically  with  the  Carpathian  and  Caucasus  ranges  and 
were  probably  formed  at  about  the  same  time. 

The  production  of  the  principal  Galician  fields  is  shown  in  tht 


REDWOOD,  BOVERTON:  A  Treatise  on  Petroleum,  vol.  1,  p.  132,  1913. 


518 


GEOLOGY  OF  PETROLEUM 


following  table.     The  positions  of  the  principal  oil  fields  are  shown 
in.  Fig.  214. 

PETROLEUM  PRODUCED  IN  GALICIA,  1913-1917,  IN  METRIC  TONS" 
(After  Northrop) 


Field 

1913 

1914 

1915 

1916 

1917 

East  Galicia: 
Tustanowice  

691  ,382 

6356  ,447 

483  ,840 

403  ,212 

Boryslaw 

205  ,904 

6116  613 

254  ,095 

247  ,926 

Schodnica 

Urycz 

Mraznica  

32  ,172 

51  ,929 

Other  fields  
West  Galicia: 
Potok 

\57S  388 

6,562 

Rogi  

190  ,000 

Rowne 

Krosno 

Tarnawa-Wielopole  - 
Zagorz 

128,563 

C120  ,000 

Kobylanka,  Kyrg,  Zala- 
wie,  Lipinki,  Lubusza, 
etc 

1  ,087  ,286 

6700  ,000 

578  ,388 

898  ,670 

829  ,629 

al  metric  ton=7.1905  barrels  of  crude  petroleum  of  42  gallons=2,204.62  pounds. 

6Figures  for  first  six  months  only. 

'Estimated. 

In  the  axis  of  the  Carpathian  Mountains1  beds  of  Cretaceous 
and  Eocene  age  ("Flysch")  crop  out.  There  is  a  narrow  sub- 
Carpathian  zone  of  the  same  rocks,  and  northeast  of  that  are  the 
Galician  plains,  which  are  covered  with  Miocene  and  later  beds. 

WALTON,  L.  V. :  A  Sketch  of  the  Geology  of  the  Baku  and  European  Oil 
Fields.  Econ.  Geology,  vol.  4,  pp.  89-113,  1909. 

UHLIG,  V.:  Ergebnisse  Geologische  Aufnahmen  in  den  Westgalizischen 
Karpathen.  K.  K.  Geol.  Reichsanstalt  Jahrb,  vol.  38,  pp.  83-264,  1888;  and 
other  papers  in  the  same  publication  by  PAUL,  TIETZE,  UHLIG,  and  others. 

GRZYBOWBKY,  J. :  On  the  Foraminifera  of  the  Oil  Sands  of  Krosno  District. 
Internat.  Acad.  Sci.  Cracovie  Bull.  1897,  pp.  180-186;  Polish  text  in  Rozpr. 
Akad.  Umiej.  Krakow,  ser.  2,  vol.  12,  pp.  256-302. 


EUROPE,  EXCEPT  RUSSIA 
PETROLEUM  PRODUCED  IN  GALICIA,  1908-1917 


519 


Year 

Metric 
Centners" 

Barrels  of 
42  Gallons 

Year 

Metric 
Centners" 

Barrels  of 
42  Gallons 

1908 

17  540  220 

12  612  ,295 

1913  

10  872  860 

7  gig  130 

1909 

20  767  400 

14  932  799 

1914 

67  000  000 

5  033  350 

1910   . 

17  625  ,600 

12  ,673  ,688 

1915  

5  783  880 

4  158  899 

1911 

14  629  400 

10  ,519  ,270 

1916.  .    .    . 

8  986  700 

6  461  706 

1912  

11  ,870  ,070 

8  ,535  ,174 

1917  

8  ,296  ,290 

5  965  447 

°1  metric  centner  or  quintal=100  kilograms  (220.462  pounds);  1  metric  centner  or  quintal 
of  crude  petroleum=0.71905  barrel  of  42  gallons. 
^Estimated. 


Cretaceou* 
differentiated) 

Principal  Oil.field* 


FIG.  214. — Geologic  sketch  of  part  of  Galicia.   (After  Dalton.) 


The   series,   including   the   lowest   petroliferous   strata,    is   as 
follows : 

Miocene: 

Sarmatian  shales,  clays,  sandstones,  limestones,  etc.,  above;  gypsiferous  and 
saliferous  clays  below. 


520  GEOLOGY  OF  PETROLEUM 

Oligocene: 

Upper,  Magura  sandstone,  Bonarowka  beds,  shales  and  hieroglyphic1  sand- 
stones, Eburna,  Melania,  Cytherea,  etc.,  Dobrotow  beds,  sandstones  and 
shales,  with  carbonized  plant  remains  in  parts,  and  abundant  Foramin- 
ifera,  generally2  petroliferous. 

Lower,  Menilite2  shales,  light  chocolate-colored,  black  or  blue  bituminous 
shales  with  fish  remains  and  Foraminifera. 

Eocene: 
Upper,  hieroglyphic  (Ciekowic)  sandstones,  greenish  and  red  shales,  etc., 

Foraminifera,  Mollusca,  Bryozoa,  and  petroleum. 
Lower,  red  clays  and  nummulitic  beds. 

Cretaceous: 

At  top,  Jamna  sandstone,  thick-bedded  or  massive,  with  "ruin"  sandstones. 

Below,  Ropianka  beds,  dark  shales  and  sandstones  at  top,  with  Neocomian 
ammonites,  Inoceramus,  fucoids,  and  petroleum.  Lower  part,  bluish 
calcareous  hieroglyphic  sandstones  (petroliferous)'  with  Inoceramus, 
fucoids,  etc.  All  these  beds  have  an  abundant  microscopic  fauna. 

lSo  called  from  the  peculiar  markings  on  the  bedding  planes. 

*So  called  from  the  presence  of  highly  siliceous  bands  ("Hornstein"). 


FIG.  215. — Section  through  Schodnica  and  Boryslaw  fields,  Galicia. 
(After  Zuber.) 

The  oil  fields  of  eastern  Galicia  are  the  most  productive.  These 
include  the  Boryslaw-Tustanowice  field  and  the  Opaka-Schodnica- 
Urycz  field.  The  positions  of  the  principal  fields  with  respect  to 
one  another  are  indicated  in  the  section  (Fig.  215). 

Boryslaw. — The  Boryslaw  field,  as  described  by  Zuber,1  lies 
close  to  the  Carpathian  Mountains  between  the  valleys  of  the 
Dniester  and  Stryj.  In  this  region  the  older  formations  are  cov- 
ered by  a  layer  of  unconsolidated  alluvial  clay  and  gravel,  at  some 
places  of  considerable  thickness.  Beneath  the  alluvial  deposits 
are  saliferous  and  associated  beds  which  consist  chiefly  of  thick 
ash-gray  clay  or  shales.  It  is  in  part  arenaceous  and  in  part  marly. 

^UBER,  RUDOLF:  Die  Geologischen  Verhaltnisse  von  Boryslaw  in  Ostga- 
lizien.  Zeitschr.  prakt  Geologie,  vol.  12,  pp.  41-48,  1904. 


EUROPE,  EXCEPT  RUSSIA 


521 


Interbedded  with  these  strata  are  irregularly  distributed  flaggy 
beds  of  sandstone,  both  fine  and  coarse  grained,  some  of  which 
contain  gas  and  oil  besides  carbonized  and  bituminous  plant 
remains.  The  plant  remains  are  found  also  in  the  shales.  The 
clays  and  shales  are  impervious  and  so  form  effective  barriers  to 
the  migration  of  oil.  The  whole  formation  is  rich  in  gypsum  and 
salt,  which  occur  as  loose  crystals,  veins  and  lenses,  and  also  in 
regular  beds.  All  the  spring  waters  from  these  beds  are  salty, 
and  some  contain  sulphur.  The  oil  that  occurs  in  the  sandstone 
beds  and  lenses  of  this  formation  is  very  irregularly  distributed. 
Layers  that  are  dry  and  barren  of  oil  are  found  in  the  immediate 


sw. 


NE. 


G.C.B. 


FIG.  216. — Section  through  Boryslaw  oil  field,  Galicia.  (After  Grzybowsky.) 
a,  Miocene;  6,  Upper  Oligocene;  c,  Lower  Oligocene;  d,  Eocene;  e,  Upper  Cre- 
taceous; G.C.B. ,  Ozokerite  mine  of  Galician  Credit  Bank. 

vicinity  of  others  that  are  richly  impregnated  with  petroleum  and 
in  places  with  ozokerite.  Ozokerite  occurs  also  in  thin-bedded 
lenses  and  as  a  filling  of  crevices  and  veins.  The  veins  are  by  far 
the  more  abundant.  (See  Fig.  216.)  They  have  been  encoun- 
tered at  depths  of  2,200  feet  in  drilling  for  oil. 

Drilling  operations  are  difficult  because  tremendous  pressure 
prevails  in  the  formation.  The  whole  earth  to  a  considerable 
depth  seems  to  move  and  shift  constantly.  The  strongest  timbers 
and  steel  pipes  are  broken  like  matches.  Whole  shafts  are  some- 
times twisted  in  corkscrew-like  fashion.  In  the  western  part  of 
the  field  the  oil  is  heavy,  viscous,  and  very  dark;  in  the  eastern 
part  it  is  lighter  in  gravity  and  color  and  is  rich  in  benzene. 

Below  the  Miocene  salt  formation  lie  the  Dobrotow  conglomer- 


522  GEOLOGY  OF  PETROLEUM 

ates,  sandstones,  and  shales,  of  late  Oligocene  age.  Beds  of  platy, 
well-hardened  argillaceous  micaceous  sandstone  predominate. 
These  show  characteristic  ripple  marks.  Here  and  there  darker 
lenses  of  shale  are  interst ratified  with  them.  The  whole  formation 
is  rich  in  carbonized  plant  remains  and  constitutes  the  richest  oil 
zone  of  the  region.  In  places  lenses  and  accumulations  of  con- 
glomerate are  interbedded,  and  these  may  become  so  extensive 
vertically  and  horizontally  that  they  displace  the  fine-grained  beds 
entirely.  The  distribution  of  the  oil  in  the  Dobrotow  formation  is 
very  irregular  and  sporadic.  Some  parts  of  the  formation  are 
absolutely  barren;  other  parts  have  delivered  large  quantities  of 
petroleum.  The  drill  records  show  a  change  in  the  formation 
from  sandstone  to  quartzite,  graywacke,  and  chlorite  slate  in  a 
northeasterly  direction.  Finally  the  conglomerates  dominate 
throughout  the  formation  and  form  a  conspicuous  outcrop  in  a  row 
of  hills  that  trend  southeast. 

Underlying  the  Dobrotow  formation  are  the  Menilitic  shales, 
of  early  Oligocene  age.  They  are  of  no  economic  importance 
unless  they  are  regarded  as  a  warning  to  drillers.  They  include 
lenses  and  beds  of  sandstone  that  contain  much  water,  which 
might  flood  the  wells  if  these  beds  were  penetrated. 

Although  the  Menilitic  shales  have  not  been  penetrated  in  the 
oil  district  (1904),  it  is  known  that  they  overlie  the  Carpathian 
Eocene  beds,  which  consist  of  red  and  green  shales  and  clays  with 
interbedded  sandstones  and  conglomerates  and  which  constitute 
some  of  the  richest  strata  in  other  fields.  It  is  highly  probable 
that  these  Carpathian  Eocene  beds  are  oil  bearing  in  this  district, 
but  they  lie  at  depths  of  perhaps  5,000  to  6,000  feet. 

The  structure  of  the  district  is  indicated  by  Figs.  215  and  216. 
The  older  formations,  including  the  Menilitic  shales,  have  been 
intensely  folded  and  partly  faulted  and  thrust  over  the  younger 
beds  along  the  edge  of  the  Carpathian  Mountains.  The  overlying 
formations  have  also  undergone  extensive  folding  and  faulting, 
but  generally  these  folds  are  short  along  the  strike  and  others 
partly  overlap  them. 

Noteworthy  features  of  this  district  are  the  large  amount  of 
ozokerite  that  has  been  formed  from  the  oil  and  the  great  depth 
at  which  the  ozokerite  is  found.  The  oil  apparently  occurs  in  both 
anticlines  and  synclines,  as  is  not  unusual  where  beds,  in  part 
incoherent,  have  been  intensely  deformed. 


EUROPE,  EXCEPT  RUSSIA  523 

Opaka-Schodnica-Urycz.-  —  The  Opaka-Schodnica-Urycz  dis- 
trict1 lies  about  8  miles  southwest  of  Boryslaw.  Oil  is  found  in 
Tertiary  and  Cretaceous  rocks  complexly  folded  and  faulted.  The 
following  formations  are  mentioned: 

5.  Tertiary.  Menilitic  shales.  Dark  bituminous  shales  with 
fish  remains  interbedded  with  sandstones.  At  the  base  of  the 
formation  are  beds  of  banded  hornstone. 

4.  Eocene.  Chiefly  green  and  red  shales  with  lenses  of  hard 
"hieroglyph"  sandstone.  Conglomerates  and  large  exotic  boulders 
are  present.  The  thick  sandstone  lenses  in  the  shale  form  one  of 
the  most  important  oil  zones  in  the  Carpathian  Mountains. 

3.  Cretaceous.  Jamna  sandstone.  A  very  massive  light-col- 
ored sandstone,  weathering  into  grotesque  forms.  Interbedded 
with  it  are  subordinate  dark  and  black  shales. 

2.  Upper  Inoceramus  beds.  Well-bedded  calcareous  sandstones 
with  "hieroglyphs"  alternating  with  dark  shales.  There  are  also 
thick  conglomerates  with  limestone.  Some  of  the  beds  contain 
carbonized  remains  and  some  of  the  sandstones  carry  petroleum. 

1.  Lower  Inoceramus  (Ropianka)  beds.  The  lower  part  of  the 
formation  consists  of  bedded  marls.  These  are  overlain  by  dark 
shales  containing  "hieroglyph"  sandstones  and  conglomerates,  in 
places  with  saline  clay  shales  and  thick  sandstone  lenses.  Some 
of  the  sandstone  lenses  carry  petroleum. 

With  the  exception  of  the  recent  diluvial  and  alluvial  deposits, 
no  rocks  younger  than  the  Menilitic  shales  are  known  in  this  dis- 
trict. No  unconformities  are  observed  between  the  different  for- 
mations, and  all  the  transitions  are  gradual. 

Intense  erogenic  movement  has  thrown  the  strata  into  a  number 
of  folds  and  faults  which  strike  northwest,  parallel  to  the  main  axis 
of  the  Carpathians.  Fig.  217  is  a  plan  of  the  field  showing  the 
positions  of  faults  and  wells  and  the  lines  of  the  cross-sections  given 
in  Figs.  218  and  219.  In  the  vicinity  of  the  line  of  section  A-B 
there  are  no  indications  of  oil.  Near  the  line  of  section  C-D  three 
bore  holes  yield  oil  from  the  Eocene  sandstones  and  conglomerates. 
The  structure  along  the  line  E-F  was  revealed  by  the  dry  well 
drilled  to  a  depth  of  1,700  feet.  At  points  marked  by  old  shafts 


RUDOLF:  Die  Geologischen  Verhaltnisse  der  Erdolzone  Opaka- 
Schodnica-Urycz  in  Ostgalizien.  Zeitschr.  prakt.  Geologie,  vol.  12,  pp.  86- 
94,  1904. 


524 


GEOLOGY  OF  PETROLEUM 


oil  springs  are  found.  A  widening  of  the  productive  zone  is  evident 
on  section  G-H.  Oil  indications  along  this  line  are  very  numerous. 
The  Eocene  oil  sands  have  been  almost  drained,  but  a  well  struck 
a  third  sand  in  the  Upper  Inoceramus  formation  (Cretaceous)  at  a 
depth  of  nearly  2,000  feet  (in  1903).  Some  of  the  wells  were  very 

productive,  and  one  yielded  about 
80,000  tons  (575,200  barrels),  an  un- 
usual quantity  for  this  field.  Section 
I-K  cuts  through  the  so-called  Zhar 
field  of  Schodnica.  Most  of  the  wells 
in  this  field  are  not  prolific,  but  they 
are  more  persistent  in  yield.  Section 
L-M  shows  the  Eocene  oil  zone  nearer 
the  surface.  In  the  deeper  beds  much 
salt  water  has  been  struck.  Along  the 
line  of  section  N-O  the  Eocene  beds  lie 
at  greater  depth.  Southeast  of  Urycz 
they  sink  still  lower. 

Nowhere  in  the  district  has  oil  been 
found  in  the  Menilitic  shales,  although 
the  shales  are  rich  in  bituminous  mat- 
ter and  fish  remains  and  inclose  a 
number  of  thick  sandstone  beds. 
Everywhere  in  this  region  the  oil- 
bearing  beds  (Eocene  and  Cretace- 
ous) are  separated  from  the  Menilitic 
shales  by  massive  impervious  beds. 
According  to  Zuber  the  hypothesis 
that  the  parent  rock  of  the  oil  is  the 
Menilitic  shale  appears  to  be  without 
foundation. 


Heavy  lines  are  fault  lines 

X  Productive  well 
o  Dry  h<jt<2 

FIG.  217.— Plan  of  Opaka- 
Schodnica  -  Urycz  oilfields, 
Galicia.  The  sections,  AB, 
etc.,  are  shown  on  Figs.  218 
and  219.  (After  Zuber.) 


Western  Galicia. — In  western  Gali- 
cia there  are  a  number  of  fields, 
among  them  Potok,  Rogi,  Rowne, 
and  Krosno.  The  oil  deposits  are  in 
Mesozoic  and  Tertiary  rocks  and  are  generally  concentrated  in 
anticlines.  On  an  anticline  at  Potok  gushers  of  high-grade  light- 
gravity  oil  have  been  brought  in.  At  Rowne  an  anticline  in 
Oligocene  beds  yields  oil  of  light  gravity. 


EUROPE,  EXCEPT  RUSSIA 


525 


RUMANIA 

Rumania,  except  Russia,  is  the  largest  producer  of  petroleum 
in  Europe.  Oil  is  found  at  many  places,  but  the  principal  deposits 
are  north  of  Bucharest,  east  and  south  of  the  Carpathian  Moun- 
tains. As  the  oil  is  of  high  grade  it  is  in  great  demand  in  European 
refineries.  Before  the  European  war  Rumania  produced  about 
12,000,000  barrels  annually. 


Fia.  218. — Sections  showing  geology   of  Zalokiec,   Opaka  and  Schodnica, 
Galicia.  The  position  of  the  sections  is  shown  on  Fig.  217.  (After  Zuber.) 

PETROLEUM  PRODUCED  IN  RUMANIA  IN  1915,  IN  METRIC  TONS 

Prahova: 

Bustenari-C  aline  t-Bor- 

deni 286  ,035  Dambovitza 100 ,824 

Campina  Poiana 120,657  Buzeu 112  ,098 

Moreni 741 ,163  Bacau 28  .931 

Other 283  ,437  Grand  total.  .                      ."  1 ,673  ,145 


Total 1,431,292 


526  GEOLOGY  OF  PETROLEUM 

Rumania  is  divided  into  three  physiographic  zones — the  Car- 
pathian Mountains,  the  foothills,  and  the  plains.  The  Carpathian 
zone1  falls  into  two  divisions — an  inner  one  occupied  by  Mesozoic 
metamorphic  and  igneous  rocks,  and  an  outer  one  occupied  by 
early  Tertiary  or  Paleogene  deposits  (Flysch  zone.)2  The  foot- 
hills are  formed  by  later  Tertiary  beds.  The  Rumanian  plain  is 
composed  of  Levantine  (Pliocene)  strata  and  the  Sarmatian  or 
Moldavian  plateau  of  Sarmatian  (Miocene)  strata.  The  oil  fields 
are  in  the  Flysch  and  foothill  regions. 

Remains  of  marine  organisms,  both  animal  and  vegetable, 
abound  in  the  early  Tertiary  (Paleogene)  and  later  Tertiary 
(Neogene)  strata.  Petroleum3  is  found  in  both  the  Eocene  and 
Miocene  rocks.  A  map  of  the  oil  region  is  shown  as  Fig.  220,  and 
a  cross-section  as  Fig.  221. 

The  following  is  a  table  of  formations:4 

Pliocene : 

Levantine.     Marls,  clays,  and  sands  with  Unio,  Vivipara,  Bythinia,  etc. 
Dacian.     Gray  shales  and  arenaceous  marls,  yellow-red  sandstone  lenses, 
fossiliferous,  3,000  to  3,500  feet  thick  (Preiswerkj. 

Pontian.  Sandstones,  gravels,  andesitic  tuffs,  sands,  and  marls;  Vivipara 
bifarcinata,  Dreissensia  polymorpha,  Congeria  rhomboidea  above;  Valen- 
dennesia  annulata  and  fish  remains  below;  petroleum  in  places  (perhaps 
from  secondary  infiltration)  and  some  beds  of  lignite. 

WALTON,  L.  V.:  Geology  of  the  Baku  and  European  Oil  Fields.  Econ. 
Geology,  vol.  4,  p.  101,  1909. 

2"Flysch  zone"  is  a  somewhat  misleading  term,  for  it  includes  beds  of  widely 
varying  age. 

3ZuBER,  R. :  Kritische  Bemerkungen  ueber  die  Modernen  Petroleum- 
Entstehungs  Hypothesen.  Zeitschr.  prakt.  Geologic,  vol.  6,  pp.  84-94,  1898. 

MURGOCI,  G.  M.:  Tertiary  Formations  of  Oltenia,  with  Regard  to  Salt, 
Petroleum,  and  Mineral  Springs.  Jour.  Geology,  vol.  13,  pp.  670-712,  1905; 
with  additions  and  corrections  in  Inst.  Geol.  Roman.  An.,  vol.  1,  1907. 

ARADI,  V.:  Erdol-Studien.  Allgem.  oesterr.  chem.  techn.  Zcitung,  vol.  26, 
1908;  Ueber  die  Bildung  der  Rumaenischen  Petroleumlagerstatten.  Organ. 
Verein  Bohrtechniker,  vol.  15,  1908. 

ANDRUSOV,  N. :  Die  Schichten  von  Kamischburun  und  der  Kalkstein  von 
Kertch  in  der  Krirn.  K.  k.  Geol.  Reichsanshalt  Jahrb.,  vol.  36,  pp.  127-140, 
1886;  Maeotische  Stufe.  Russ.  k.  min.  Gesell.  Verh.,  ser.  2,  vol.  43,  pp.  289- 
450,  1905. 

STEFANESCU,  S. :  Etude  sur  les  Terrains  Tertiaires  de  Roumanie,  Lille,  1897. 

4DALTON,  L.  V.:  Op.  cit.,  p.  102,  with  modifications  to  conform  with  later 
descriptions  of  Preiswerk  and  others. 


EUROPE,  EXCEPT  RUSSIA 


527 


Miocene: 

Maeotic.     Limestone  with  Dosinia  exoleta,  sandy  clays,  fine  sand  and  blue 

clays  with  Hydrobia,  etc.,  and  small  Congeriae  at  top.     Petroliferous. 
Sarmatian.     Marls  and  oolitic  limestones  with  Tapes  gregaria,  Bucdnium 

duplicatum  or  Ervilia  podolica,  Mactra  podolica,  etc. 
Tortonian.     Limestones,  marls,  conglomerates,  sands,  and  tuffs,  in  places 

with  Ostrea  cochlear.     Gypsum  and  some  petroleum. 
Helvetian.     Marls,  laminated  micaceous  sandstones,   gypsum,   salt,  and 

tuffs.     Ostrea,  Lithothamniiim.      Petroleum. 
Burdigalian.     Clays,   conglomerates,   tuffs.     Cerithium  margaritaceum,   C. 

plicatum,  Ostrea  crassissima,  etc.     Lignite  in  parts,  petroleum. 

Oligocene: 

Sands,  sandstones,  conglomerates,  shales,  varying  in  different  parts  of  the 
country,  with  Nodosaria,  Cerithium,  f ucoids.  Petroleum. 

Eocene : 

Ordinary  marine  facies  found  in  the  Dobrudja  and  here  and  there  in  the 
Carpathians,  as  limestones  with  Nummulites  distans,  N.  irregularis. 
Represented  by  upper  parts  of  Flysch. 


(359  Upper  Inoceramus  bects\  « 
|5^gl  Lower  Inocerarni'S  ^eofej"^  |' 

0  *^  /OOP1 


ffcnMh'c  shak!>(0ligocen<>l 
'ccene 

2000 


FKJ.  219. — Sections  showing  geology  of  Schodnica  and  Urycz,  Galicia.  The 
position  of  the  sections  is  shown  on  Fig.  217. 


528  GEOLOGY  OF  PETROLEUM 

In  the  Rumanian  Carpathians  five  earth  movements  have  taken 


FIG.  220. — Map  of  part  of  Rumania.   (After  Dalton.)  Since  this  map  was 
made  oil  fields  have  been  developed  between  Buzeu  and  Bacau. 

place — (1)  at  the  end  of  the  Cretaceous,  so  that  the  lower  parts  of 


EUROPE,  EXCEPT  RUSSIA 


529 


the  Flysch  are  unconformable  on  the  upper  parts;  (2)  between 
Oligocene  and  Tortonian  time;  (3)  after  the  Tortonian,  when  the 
sea  advanced  over  the  older  rocks;  (4)  in  Pontian  time,  when  the 
present  higher  lands  began  to  form;  and  (5)  in  post-Levantine 
time.  There  are  extensive  overlaps,  the  Pontian  resting  on  the 
Tortonian  at  one  place  and  on  the  crystalline  rocks  at  another. 


FIG.  221. — Section  through  "Flysch"  zone,  Trotus  Valley,  Moldavia, 
a,  Paleogene  salt  beds;  6,  Jargu  Ocna  beds;  c,  Lower  Menilite  shales,  Schipot 
beds;  d,  Upper  Menilite  shales,  Jisesti  sandstone;  E,  Miocene  (Helvetian) 
salt  beds.  (After  Zuber.) 

In  general,  however,  as  the  beds  dip  away  from  the  Carpathian 
chain,  they  occupy  belts,  the  outermost  being  the  youngest. 
There  is  also  a  southward  dip  from  Moldavia  into  Wallachia,  the 
younger  beds  lying  to  the  southeast.  The  beds  are  complexly 
folded  and  faulted,  and  the  folds  lie  parallel  to  the  Carpathian 
chain.  As  a  rule  the  folds  are  asymmetric,  the  gentler  dips  lying 
on  the  sides  toward  the  plains.  Overturned  folds  are  common. 


V.N.W. 


FIG.  222. — Section  along  Prahova  River,  Cornu  and  Doftanitya  Valley, 
a,  Flysch:  b,  Helvetian  (Miocene  salt  series);  c,  Sarmatian;  d,  Pontian.  (After 

Stefanescu.) 

In  the  Prahova  district  the  principal  folds  are  those  of  Bustenari- 
Campina-Draganeasa  (Figs.  222  and  223)  and  the  one  on  which 
are  the  fields  of  Tzintea,  Baicoi  (Fig.  224),  and  Moreni  (Fig.  225). 
The  Bustenari  fold  is  an  overturned  fold  of  the  Maeotic  (Miocene) ; 
the  axial  plane  dips  south,  and  the  whole  is  faulted  down  on  the 
north  side  at  Campina  against  the  Helvetian.  The  oil  of  Campina 


530 


GEOLOGY  OF  PETROLEUM 


is  believed  to  be  derived  from  the  Sarmatian.  At  Bustenari, 
according  to  Andrusov,  the  wells  started  in  the  Maeotic  pass  into 
unconformable  Oligocene  below.  .Thick  salt  deposits  are  found 
in  some  of  the  domes. 


NNW 


SSE 


Salt 


S,    Sarmatian;     /,    Sub-Carpathian    salt    formation; 

o,    Oligocene;    e,    Eocene;    m,    Meotic;    C,  Congeria  beds,* 

FIG.  223. — Section  across  Faget  Bustenari,  Rumania.  (After  Thompson.) 

The  Berca  and  Beciu  fields1  are  20  kilometers  from  the  city  of 
Buzeu,  in  a  region  which  is  well  known  for  its  active  mud  volcanoes. 
They  are  on  an  anticline  that  strikes  north-northeast  and  has  been 
traced  for  30  kilometers.  The  mud  volcanoes  themselves  are  con- 


NNW 


a,    Bifarcinates  beds;        6,    Rock  salt;  c,    Congeria  beds; 

d,     Candesti  beds, 
FIG.  224. — Section  through  Baicoi  oil  field,  Rumania.  (After  Thompson.) 

fined  to  a  stretch  of  12  kilometers  in  the  central  part  of  the  anti- 
cline (Fig.  226),  where  oil  seeps  and  efflorescent  salts  are  common. 
The  outcropping  rocks  of  the  region  are  all  of  middle  or  late 
^REISWERK,  H. :  Ueber  den  Geologischen  Bau  der  Region  der  Schlamm- 
vulkane  und  Olfelder  von  Berca  und  Beciu  bei  Buzeu  in  Rumanien.     Zeitschr. 
prakt.  Geologic,'  vol.  20,  pp.  86-95,  1912. 


EUROPE,  EXCEPT  RUSSIA 


531 


Tertiary  age,  beginning  with  the  youngest  formation,  the  Levan- 
tine, through  the  Dacian  and  Pontian,  to  the  oldest,  the  Maeotic. 
The  Levantine  consists  of  sands  and  marls  with  numerous  seams 
of  lignite,  which  reach  a  thickness  of  6  to  7  inches,  in  the  lower  part 
of  the  formation. 

The  underlying  Dacian  is  estimated  to  be  3,000  to  3,500  feet 
thick.  Gray  shales  and  arenaceous  marls  prevail.  Interbedded 
with  them  occur  lenses  and  beds  of  hard  yellow-red  sandstone  that 
is  rich  in  fossils.  The  abundance  of  fossils  in  the  whole  formation 
makes  its  recognition  in  the  field  relatively  easy. 

Beneath  the  Dacian  lie  the  Pontian  sediments,  which  occupy 
large  areas  in  this  district.  Four  groups  are  distinguished,  as 
follows:  Yellow  sandstones,  more  or  less  consolidated,  200-300 
meters;  gray  clay  marl,  200  meters;  yellow  sands  and  sandstones, 
the  latter  with  spherical  concretions  and  ripple  marks,  100  meters; 
gray  clay  marls,  100  meters.  All  these  divisions  contain  fossils. 


Moreni 


«,  Quaternary;       I,  Levantine;    d,  Dacian;        P,    Pontian; 
m,  Meotic;    s,  Sarmatian;       s&,    Miocene  salt  formation 
FIG.  225. — Section  through  Moreni  oil  field,  Rumania.  (After  Thompson.) 

The  oil-bearing  strata  are  in  the  Maeotic,  which  has  a  thickness 
of  about  600  meters.  Marls  and  sands  constitute  the  main  mass 
of  the  formation.  Interbedded  with  these  are  fairly  hard  sand- 
stones, which  make  good  horizon  markers  on  account  of  their 
superior  resistance  to  erosion.  Toward  the  base  of  the  formation 
they  become  more  calcareous. 

The  Maeotic  formation  is  the  lowest  of  the  series  described  by 
Preiswerk  as  cropping  out.  Underlying  it  is  the  Sarmatian  forma- 
tion of  Mactra  limestone  and  rather  coarse  sandstones  and  con- 
glomerates, so  far  unexplored  in  this  district. 

The  structure  of  the  district  is  shown  in  the  accompanying 
sections  (Fig.  226).  The  anticline  is  steep  and  asymmetric.'  The 
mud  volcanoes  are  situated  in  the  central  depression  which  sug- 


532 


GEOLOGY  OF  PETROLEUM 


gests  a  fault  or  rupture  of  some  sort  in  the  strata.  The  principal 
oil  zone  in  the  Maeotic  formation  lies  about  250  meters  below  the 
top  bed  of  the  formation.  Up  to  1912  no  attempt  had  been  made 


Pliocene 


Well! 


Dact'an 


I      I  Mcreotic 


$a It  formation 

\ 


Well4 
We/A 


FIG.  226. — Sections   through   Berca   and   Becieu  oil  fields,  Rumania.  (After 

Prieswerk.) 

to  drill  into  the  Sarmatian,  the  Miocene  salt  formation  beneath, 
although  the  Miocene  has  proved  highly  productive  in  other 
Rumanian  fields. 


CHAPTER  XXV 

RUSSIA,  MESOPOTOMIA,  PERSIA  AND  EGYPT 
RUSSIA 

General  Features. — In  Russia  oil  occurs  in  many  widely  sep- 
arated fields.  These,  named  from  north  to  south,  as  listed  by 
Adiassevich,1  are  as  follows: 

1.  Basin  of  Petchora  River,  northern  Russia. 

2.  Volga  basin,  in  governments  of  Samara  and  Saratoff. 

3.  Astrakhan  and  Ural  governments,  northeast  shore  of  Cas- 
pian Sea. 

4.  Grozny  and  Maikop. 

5.  Derbend  district,  Daghestan,  north  of  Baku,  on  Caspian  Sea. 

6.  Baku  fields. 

7.  Sviatoi  (Holy  Island)  and  Cheleken  islands,  in  Caspian  Sea. 

8.  Neftianoia  Gora  (Oil  Hill),  in  Transcaspian  territory. 

9.  Ferghana  Valley,  Russian  Central  Asia. 

10.  Kertch  and  Taman  peninsulas,  Black  Sea. 

11.  Sakhalin  and  Transbaikal,  Siberia. 

Of  these  districts  the  Baku  fields  are  by  far  the  most  productive, 
although  considerable  oil  is  produced  also  in  Grozny  and  Maikop. 
These  fields  are  on  the  flanks  of  the  Caucasus  Mountains,  which 
constitute  a  high  range  north  of  the  Black  Sea,  extending  south- 
eastward to  near  the  Caspian.  The  range  is  anticlinal  in  structure2 
and  is  practically  in  line  with  the  Apsheron  peninsula.  The 
central  mass  of  the  range  is  granite,  which  is  skirted  by  diabase, 
and  that  in  turn  by  Paleozoic  metamorphosed. rocks.  The  sedi- 
mentary rocks  that  rest  upon  the  ancient  rocks  are,  in  order,  the 
Triassic,  Jurassic,  Lower  Cretaceous,  Upper  Cretaceous,  and  Ter- 
tiary (Flysch,  etc.)  The  fields  of  Taman  and  Kertch  peninsulas, 
on  the  north  shore  of  the  Black  Sea,  are  at  the  west  end  of  the 
range.  The  Baku  fields  are  at  the  east  end,  Maikop  and  Grozny 
on  the  north  slopes,  and  Tiflis  on  the  south  slope. 

ADIASSEVICH,  A.:  Oil  Fields  of  Russia.  Am.  Inst.  Min.  Eng.  Trans.,  vol. 
48,  p.  613,  1914. 

2Carte  geologique  Internationale  de  1' Europe. 

533 


534 


GEOLOGY  OF  PETROLEUM 


PETROLEUM    PRODUCED  IN  RUSSIA,  1907-1917 
(After  Northrup) 


Year 

Baku 

Grosny 

Maikop 

Poods  a 

Barrels 

Poods 

Barrels 

Poods 

Barrels 

1907 

476  ,002  ,000 
465  ,954  ,221 
492  ,500  ,000 
508,456,121 
454  ,206  ,853 
473  ,200  ,000 
404  ,538  ,000 
412  ,246  ,851 
431  ,139  ,305 
464  ,902  ,000 
413  ,000  ,000 

57  ,143  ,097 
55  ,936  ,880 
59  ,123  ,650 
61  ,039  ,149 
54  ,526  ,633 
56  ,806  ,723 
48  ,563  ,985 
49  ,489  ,418 
51  ,757  ,419 
55  ,810  ,564 
49  ,560  ,000 

39  ,214  ,612 
52  ,058  ,895 
57  ,033  ,015 
74  ,048  ,358 
75,189,591 
65  ,400  ,000 
73  ,659  ,265 
98,445,187 
88,159,052 
102  ,731  ,246 
123  ,000  ,000 

4  ,707  ,637 
6  ,249  ,567 
6  ,846  ,700 
8  ,889  ,359 
9  ,026  ,361 
7  ,851  ,140 
8  ,842  ,649 
11,818,150 
10  ,583  ,320 
12  ,332  ,683 
14  ,760  ,000 

1Q08 

1909 

1910.  .  . 

1  ,304  ,800 
7  ,933  ,936 
9  ,200  ,000 
4  ,802  ,926 
3  ,956  ,906 
7  ,582  ,000 
2  ,000  ,000 
(<*) 

156  ,640 
952  ,453 
1,104(442 
576  ,582 
475  ,019 
910  ,204 
240  ,096 
<d) 

1911 

1912  

1913 

1914  

1915 

19166  

191?c 

°61.05  poods=l  metric  ton  crude;  8.33  poods  crude=l  United  States  barrel  of  42  gallons; 
8  poods  illuminating  oil=l  United  States  barrel  of  42  gallons;  8.18  poods  lubricating  oil=l 
United  States  barrel  of  42  gallons;  9  poods  re3iduum=l  United  States  barrel  of  42  gallons; 
7.50  poods  naphtha=l  United  States  barrel  of  42  gallons;  8.3775  poods  other  products=l 
United  States  barrel  of  42  gallons,  estimated;  1  pood=36.112  pounds;  1  kopeck=0.515  cents. 

^Estimated  in  part. 

Estimated. 

^Included  in  other. 


Year 

Einba 

Other 

Total 

Poods 

Barrels  of 
42  Gallons 

Poods 

Barrels  of 
42  Gallons 

Poods 

Barrels  of 
42  Gallons 

1907 

515,216,612 
518,013,116 
549  ,533  ,015 
585  ,903  ,660 
551,310,151 
566  ,600  ,000 
523,410,191 
558  ,280  ,944 
571  ,005  ,357 
606  ,433  ,246 
575  ,000  ,000 

61  ,850  ,734 
62  ,186  ,447 
65  ,970  ,350 
70  ,336  ,574 
66,183,691 
68  ,019  ,208 
62  ,834  ,356 
67  ,020  ,522 
68  ,548  ,062 
72,801,110 
69  ,000  ,000 

1908 

1909  

1910 

«2  ,094  ,381 
613  ,979  ,771 
'18  ,800  ,000 
<*33  ,228  ,000 
26  ,957  ,000 
27  ,493  ,000 
21  ,600  ,000 
16  ,000  ,000 

251  ,426 
1  ,678  ,244 
2  ,256  ,903 
3  ,988  ,956 
3,236,134 
3  ,300  ,480 
2  ,593  ,037 
1  ,920  ,000 

1911  

1912  

1913  
1914  
1915  

7,182,000 
16  ,675  ,000 
16  ,632  ,000 
15  ,200  ,000 
15  ,000  ,000 

862  ,184 
2  ,001  ,801 
1  ,996  ,639 
1  ,824  ,730 
1  ,800  ,000 

1916*  
1917/  

°Includes  as  follows:  Sviatoi,  1,392,306  poods;  Ferghana,  610,500  poods,  and  Taman, 
91,575  poods. 

6Includes  as  follows:  Sviatoi,  2,515,363  poods;  Cheleken,  10,205,740  poods;  and  Ferghana, 
610,500  poods;  other  districts,  648,158  poods. 

Includes  as  follows:  Sviatoi,  3,300,000  poods;  Cheleken,  13,300,000  poods;  and  Ferghana, 
2,200,000  poods. 

^Includes  as  follows:  Sviatoi,  4,733,000  poods;  Balakhani,  13,860,000  poods;  Berekei, 
6,000,000  poods;  Ferghana,  1,406,000  poods;  and  Cheleken,  7,229,000  poods. 

'Estimated  in  part. 

/Estimated. 


RUSSIA,  MESOPOTOMIA,  PERSIA  AND  EGYPT    535 


PETROLEUM  PRODUCED  FROM  PUMPING  AND  FLOWING  WELLS  IN  RUSSIA  IN 
1916  AND  1917    (After  Northrup) 


District 

1916a 

19176 

Barrels 

Poods 

Barrels 

Poods 

Apsheron  Peninsula  or  Baku: 

10  ,204  ,082 
12  ,004  ,802 
6  ,962  ,785 
10  ,768  ,307 
4,141,056 
11  ,729  ,532 

85  ,000  ,000 
100  ,000  ,000 
58  ,000  ,000 
89  ,700  ,000 
34  ,495  ,000 
97  ,707  ,000 

33  ,000  ,000 

3  ,360  ,000 
13  ,200  ,000 

275  ,000  ,000 

28  ,000  ,000 
110,000,000 

Sabunchy      ,                      

Bibi-Eibat  

55  ,810  ,564 
12  ,332  ,683 
1  ,824  ,730 
840  ,336 
240  ,096 
240  ,096 
360  ,144 

|  1,152,461 

464  ,902  ,000 
102  ,731  ,246 
15  ,200  ,000 
7  ,000  ,000 
2  ,000  ,000 
2  ,000  ,000 
3  ,000  ,000 

9  ,600  ,000 

49  ,560  ,000 
14  ,760  ,000 
1  ,800  ,000 
960  ,000 

1  ,920  ,000 

413  ,000  ,000 
123  ,000  ,000 
15,000,000 
8  ,000  ,000 

16  ,000  ,000 

Emba                                   '                     .... 

Ferghana               

Cheleken                               

Balakhany  (hand  wells) 

Schubany  (hand  wells)  
Grand  total                     

72,801,110 

606  ,433  ,246 

69  ,000  ,000 

575  ,000  ,000 

Baku. — Baku,1  on  the  Apsheron  Peninsula  (Fig.  227),  lies  ap- 
proximately on  the  line  of  the  axis  of  the  Caucasus  Mountains. 
All  its  outcropping  rocks  are  of  Tertiary  age.  The  oldest  rocks, 
which  are  Eocene,  are  exposed  in  the  western  part  of  the  peninsula. 
East  of  them  to  the  vicinity  of  Balakhany,  Miocene  rocks  are 
exposed.  Still  farther  east  are  Pliocene  rocks,  consisting  of  the 
Baku  group  and  the  underlying  Apsheron  group.  The  north  and 
east  coasts  of  the  peninsula  are  covered  with  alluvium.  The 
Tertiary  beds  are  folded  and  locally  faulted.  As  summarized 
by  Dalton,  the  formations  are  given  below:2 

aThis  description  of  the  Baku  fields  is  a  digest  of  the  papers  cited  below. 
The  data  are  drawn  principally  from  ADIASSEVICH,  DALTON,  SJOGREN,  THOMP- 
SON, and  REDWOOD.  I  have  not  had  access  to  the  paper  by  SJOGREN  published 
in  the  Geol.  Foren.  Stockholm  Forh.  14,  p.  387,  1892.  A  good  abstract  of  this 
paper  appeared  in  the  Zeitschr.  prakt.  Geologie,  1894,  pp.  286-289.  I  have 
added  a  number  of  other  references  to  papers  cited  by  DALTON,  which  were  not 
accessible  to  me. — W.  H.  E. 

2DALTON,  L.  V. :  A  Sketch  of  the  Geology  of  the  Baku  and  European  Oil 
Fields.  Econ.  Geology,  vol.  4,  89-117,  1909. 

ANDRUSOV,  N.:  Beitrage  zue  Kenntniss  des  Kaspischen  Neogen.  Com. 
G6ol.  Mem.,  vol.  15,  No.  4,  1902. 

ANDRUSOV,  N.:  Die  Siidrussischen  Neogenablagerungen.  Russ.  k.  min. 
Gesell.,  Verh.,  ser.  2,  vols.  34,  36,  39,  1897-1902.  On  the  Paleogene,  SOKOLV, 
N.,  Com.  geol.  Mem.,  vol.  9,  No.  2,  1893. 

ADIASSEVICH,  A  :  The  Russian  Oil  Fields.  Am.  Inst.  Min.  Eng.  Bull.  89, 
pp.  855-868,  1914. 

THOMPSON,  A.  B. :  The  Oil  Fields  of  Russia,  London,  1904. 


536 


GEOLOGY  OF  PETROLEUM 


FIG.  227. — Geologic  sketch  map  of  Apsheron  peninsula,  Baku  field,  Russia. 

(After  Sjogren.) 


RUSSIA,  MESOPOTOMIA,  PERSIA  AND  EGYPT    537 

Quaternary: 

Caspian  beds  (sands)  above,  with  Cardium  edule,  Helix  limestones  near  the 
top.  Aralo-Caspian  below,  with  Cardium,  etc. 

Pliocene : 

Upper.     Shell  limestones;  marls  and  sands,  with  Cardium  crassum,  Dreis- 

sensia  polymorpha. 
Lower  (unconformable  to  above).     Grits,  shales  and  volcanic  sands  passing 

up  into  limestones  (Cardium,  Micromelania,  Cypris,  Dreissensia)  in  east; 

in  west,  limestones  with  Congeria,  Dreissensia,  etc.  In  places  unconform- 
able to  Miocene  below. 
Miocene : 

Maeotic.     Sandy  limestones,  marls,  and  petroliferous  sands,  with  Aktchagil 

fauna,  small  Mactra,  Cardium,  Cerithium,  and  calcareous  algae. 
Sarmatian.     Calcareous  petroliferous  sandstones,  gypseous  marls,  sands, 

etc.,  Cardium,  ostracodes.     Overlaps  the  Helvetian  and  Tortonian. 
Helvetian  and  Tortonian.     Spaniodon  beds  (marls,  sands,  and  sandstones 

with  S.  barboti,  etc.)  above  Tchokrak  beds,  sandy  and  marly  deposits, 

with  Dentalium,  Lucina,  etc.,  and  limestones  with  Pecten,  Chama,  and 

Bryozoa. 
Burdigalian.     Upper  part  of  series  of  shales,  etc.,  with  Meletta,  Spirialis, 

etc.,  and  in  Kertch  Burdigalian  fossils. 

Oligocene : 

On  north  side  of  Caucasus,  continuous  series  of  shales,  few  fossils,  Burdig- 
alian at  top,  Tongrian  lower. 

On  south,  tuffs,  breccia,  conglomerate  (Aquitanian),  clayey  and  calcareous 
sandstones  with  Mollusca  (Tongrian),  calcareous  and  clayey  sandstones 
with  marine  fossils  (Ligurian). 

Eocene : 

Bartonian.     White  marls  with  Mollusca  and  Foraminifera  in  Crimea  and 

northwest  Caucasus;  shaly  clays  with  fish  remains,  etc.,  elsewhere. 
Parisian.     Dark-gray  foraminiferal  clays  in  west  and  north;  yellowish 

calcareous  clayey  marine  sandstones  on  south. 
Londinian.     Marls  and  limestones  with  nummulites,  fucoids,  etc.,  in  north 

and  west;  clayey  fucoidal  sandstones,  dark-gray  shales,  and  marls  and 

limestones  on  south. 

In  the  Baku  field  (Fig.  228), l  on  the  mainland,  the  post-Tertiary 
deposits  comprise  loess,  loam,  sands,  gravels,  and  silts,  with  marine 
deposits  of  friable  shelly  limestone.  The  Pliocene  has  a  total 
thickness  of  1,225  feet  and  is  divided  into  the  lower  and  upper 
stages.  The  Miocene  deposits,  mainly  sands,  clays,  and  marls, 
belong  to  the  Aktchagil  series. 

^DIASSEVICH,  A. :  The  Russian  Oil  Fields.  Am.  Inst.  Min.  Eng.  Bull.  89, 
pp.  855-868,  1914. 


538 


GEOLOGY  OF  PETROLEUM 


FIG.  228.— Map  of  Baku  oil  field,  Russia.   (After  Adiassevich.) 


RUSSIA,  MESOPOTOMIA,  PERSIA  AND  EGYPT    539 

Under  these  series  lie  the  oil  measures,  some  5,600  feet  thick. 
They  consist  of  gray,  blue,  and  brown  clays,  with  sands  and  thick 
marls  interstratified  with  sands.  The  upper  part  of  these  deposits 
contains  marine  and  lacustrine  fauna;  in  the  lower  part  no  fossils 
have  been  found.  The  oil  measures  are  underlain  by  sandy  clays 
and  striated  clays.  The  oil  is  heavy  and  is  accompanied  by  much 


HH£ 


[=!  Clays,  and  marts 
ESj  Oil-bearing  strain 
£r^[  Sands  and  sandstones   }(Mi<K*"*) 

FIG.  229. — Anticline  between  Pouta  and  Perin-Agit  Hill,  Baku  oil  field,  Russia- 


Lirnestones,clays  and  Sana's 
Ap&herion  (Pliocene) 
\        I  Marly  shales  and  sc*ndi>\  Balakhany 


gas.  The  greater  portion  of  the  oil  produced  has  come  from 
gushers,  although  pumped  wells  also  have  been  profitable.  Some 
of  the  gushers  yield  large  quantities  of  sand  along  with  the  oil,  and 
the  removal  of  the  sand  at  the  mouths  of  wells  is  a  serious  problem. 1 
The  Tertiary  beds,  which  form  anticlinal  and  synclinal  folds 
and  dome-shaped  uplifts,  are  cut  in  several  directions  by  faults. 
The  general  trend  of  uplifts  on  the  peninsula  corresponds  to  the 
direction  of  the  main  Caucasus  Range,  from  northwest  to  south- 
east. (See  Figs.  229,  230.) 


sw 


2 


1  Miles 


Horizontal  and  vertical  scale 

FIG.  230. — Synclinorium  crossing  the  village  of  Khirdalan,  Baku  oil  field, 
Russia.   (After  Redwood.)  Legend  same  as  in  Fig.  229. 

West  of  Holy  Island,  on  the  mainland,  is  the  Kala  anticline,  and 
west  of  that  the  Balakhany-Sabunchy-Romany  anticline.  Accord- 
ing to  Adiassevich  the  Balakhany  fold  is  an  elongated  dome. 

I!VNAPP,  A.:  Problems  Connected  with  the  Recovery  of  Petroleum  from 
UnconscHdated  Sands.  Am.  Inst.  Min.  Eng.  Bull.  123,  p.  385, 1917. 


540  GEOLOGY  OF  PETROLEUM 

Along  the  line  of  the  main  uplift  is  a  series  of  mud  volcanoes, 
many  of  which,  even  at  the  present  time,  spout  mud  and  water, 
gases,  and  petroleum.  The  mud  volcano  Bog-Boga  is  one  of  the 
highest  points  in  the  region.  Oil,  gas,  and  mud  still  issue  from 
little  cones  on  it,1  and  solid  pitch  is  dug  from  one  side  of  it.  These 
fields  have  borne  the  names  of  the  three  villages,  although  they 
have  long  since  merged  into  one  continuous  field  covering  some 
1,978  acres.  From  this  territory  has  come  the  main  part  of  the 
Russian  oil. 

In  the  Balakhany-Sabunchy-Romany  field  the  producing  strata 
are  Oligocene  and  Miocene.  There  are  three  divisions  of  oil-bear- 
ing sands.  The  topmost  has  a  thickness  of  1,225  feet  including 
the  interbedded  clays ;  the  thickness  of  the  pay  sands  alone  is  about 
600  feet,2  and  individual  pay  sands  range  from  several  feet  to  70 
feet.  This  first  division  is  separated  from  the  second  by  thick 
water-bearing  sands  and  sandstones.  The  second  oil  division  has 
a  total  thickness  of  some  600  feet  and  comprises  280  feet  of  oil 
sands.  Below  these  is  the  lowest  and  thickest  division. 

A  short  distance  east  of  the  Balakhany  field  lies  the  Surakhany 
field,  which  ever  since  the  fire  worshippers  days  has  been  known 
as  a  gas  field.  In  late  years  large  amounts  of  light  oil  have  been 
discovered  and  many  big  gushers  brought  in.  Nearly  all  wells 
sunk  below  1,400  feet  are  gushers.  The  field  is  a  dome-shaped 
anticline  striking  north. 

At  Binagady,  about  5  miles  northwest  of  Balakhany,  marine 
Miocene  shales  and  sands  are  exposed  near  the  center  of  a  faulted 
anticline.  The  sands  are  sealed  by  faulting,  and  oil  accumulates 
near  the  faults  (Fig.  53,  p.  146). 

The  Bibi-Eibat  field,  which  is  also  one  of  the  most  productive 
in  the  world,  lies  3  miles  south  of  Baku  and  covers  an  area  of  about 
1,000  acres.  Oil  and  gas  seeps  mark  the  surface,  and  mud  vol- 
canoes are  found  near  by.  Structurally  the  field  is  an  almost 
symmetrical  anticline.3  The  arching  beds  of  the  Miocene  just 
reach  the  surface4  (Fig.  231)  and  are  flanked  by  imposing  escarp- 

irTHOMPSON,  A.  B. :  Oil-field  Development,  p.  187,  London,  1916. 
2Other  estimates  are  considerably  lower. 

3TnoMPSON,  A.  B. :  Oil-field  Development,  p.  226,  London,  1916. 
THOMPSON,  A.  B. :  The  Relationship  of  Structure  and  Petrology  to  the 
Occurrence  of  Petroleum.     Inst.  Min.  and  Met.  Trans.,  vol.  20,  p.  220,  1911. 


RUSSIA,  MESOPOTOMIA,  PERSIA  AND  EGYPT    541 

ments  of  the  Apsheron  limestones.  The  anticline  plunges  down- 
ward on  its  landward  side  and  is  believed  to  plunge  downward  on  a 
fourth  side  where  covered  by  the  sea.  The  Bibi-Eibat  field  has 
produced  petroleum  since  1880.  In  1912  it  had  yielded  280,500,000 
barrels.  All  the  deep  waters  in  the  district  are  brines. 

Grozny. — The  Grozny1  oil  field  is  west-northwest  of  Grozny, in 
the  Terek  basin,  on  the  north  side  of  the  Caucasus  Mountains. 
It  is  in  a  range  of  hills  15  miles  long  that  strike  west-northwest  and 
do  not  exceed  660  feet  in  elevation.  This  range  is  regarded  by 
some  as  a  spur  of  the  Sunzha  massif.  It  is  a  sharp  anticline,  the 
crest  of  which  lies  along  the  northeast  flank  of  the  range.  The 
oldest  beds  crop  out  in  the  center  of  the  range  and  dip  away  from 


sw.  _ 


/VE. 


•a,  ApsheroK  bedsj  b>  Fresh  water  beds  (upper Miocene);  m)  M encof 1C 
Scale:  i  —  '  ' 

FIG.  231. — Section  of  the  Bibi-Eibat  oil  field,  Baku,  Russia.  (After  Thompson. ) 


it  quaquaversally,  the  steepest  dips  being  north  and  south.  The 
north  limb  dips  40°  to  90°;  the  south  dip  is  considerably  lower 
(Fig.  40,  p.  134).  The  oil  is  found  in  the  Miocene  sands  of  the 
Chokrak.  The  section  of  the  rocks,  after  Kalitzky,  follows: 


SECTION  OF  STRATA  IN  GROZNY  FIELD,  CAUCASUS,  RUSSIA 

Maeotic  stage: 

Aktchagil  beds,  limestone,  limestone  conglomerates,,  calcareous 

sandstones,  clayey  sands,  and  calcareous  clays 

Break. 


Feet 
1,395 


JKALITZKY,  K. :  Das  Naphtagebiet  von  Groznyj.  Com.  geol.  Russie  Mbm., 
new  ser.,  No.  24,  pp.  1-40,  1906;  Abstract  in  Inst.  Min.  Eng.  Trans.,  vol.  35, 
pp.  743-744,  London,  1908.  (The  original  paper  is  not  accessible  to  me. — 
W.  H.  E.) 


542  GEOLOGY  OF  PETROLEUM 

Middle  Sarmatic  stage:  Feet 

Gray  shales,  with  occasional  thin  flaggy  limestones 130-1  ,050 

Calcareous  clays,  with  limestones  in  the  upper  portion  of  the 

group 312 

Lower  Sarmatic  stage: 

Calcareous  clays  with  intercalations  of  chalklike  marl 56 

Calcareous  and  shaly  clays,  with  interbedded  limestones 141 

Passage  beds: 

Spaniodontella  beds,  shaly  and  sandy  clays,  clayey  limestones, 
calcareous  clays  and  sandstones,  pure  sandstones  (all  sand- 
stones water  bearing),  and  limestones 164 

Chokrak  beds,  shaly  and  sandy  clays,  petroleum-bearing  sand- 
stones (clayey,  calcareous,  etc.),  limestones  (in  places  nodular), 
dolomites. 1 ,214 

Mediterranean  stage: 

Spirialis  beds,  black  shaly  clays,  limestones,  black  nodular  lime- 
stones, dolomites (?) 

There  are  several  oil-bearing  sands  sealed  by  clays.  The  axial 
plane  df  the  dome  dips  south.  The  greatest  accumulations  are  on 
the  flat  Jimb  of  the  fold,  especially  in  the  lower  beds. 

Maikop.— The  Maikop1  oil  field,  in  the  Kuban  province,  Russia, 
is  about  300  miles  west  of  Grozny,  on  the  north  slope  of  the  Cau- 
casus Mountains.  It  is  about  50  miles  northeast  of  Tuapse,  on  the 
Black  Sea.  Cretaceous  beds  are  thrown  into  gentle  folds  and 
resting  unconformably  upon  them  are  Tertiary  beds  which  dip 
uniformly  at  low  angles. 

The  lower  Oligocene  is  composed  chiefly  of  Foraminifera  beds, 
which  are  said  to  be  unfavorable  for  oil. 2  Above  the  Foraminifera 
beds  are  lenses  of  sand,  as  much  as  56  feet  thick,  that  contain 
light  oil.  One  lenticle  70  acres  in  extent  yielded  400,000  tons  of 
oil.  The  two  heavy-oil  zones  in  the  Maikop  strata  crop  out  in 
places.  The  lower  zone  has  yielded  a  gushing  well.  The  sands 
are  thick,  and  where  they  crop  out  they  are  so  impregnated  with 
oil  that  when  the  sand  is  squeezed  in  the  hand  oil  oozes  out  like 
water  from  a  sponge. 3  In  places  the  oil  rises  to  the  contact  of  the 
oil  sand  with  the  Cretaceous  beds  (Fig.  57,  p.  150). 

BALDER,  WILLIAM:  The  Maikop  Oil  Field,  South  Russia.  Inst.  Min.  Eng. 
Trans.,  vol.  48,  pp.  321-347,  1915. 

"THOMPSON,  A.  B.:  Inst.  Min.  and  Met.  Trans.,  vol.  20,  p.  258, 1911. 

'TRENCH,  R.  H. :  Discussion  of  THOMPSON'S  paper.     Op.  cit.,  p.  247. 


RUSSIA,  MESOPOTOMIA,  PERSIA  AND  EGYPT    543 


TERTIARY  FORMATIONS  AT  MAIKOP,  RUSSIA 
(After  Rappoport)a 


Series 

Stage 

Lithologic  Character  and 
Subdivision  of  Strata 

Fossils 

Lower  Mio- 
cene. 

Maikop  stage. 

1.  Dark    laminated    noncalcareous 
clays. 
2.  Nef  tyanoya  heavy-oil  zone,  alter- 
nating sands  and  clays,  out- 
cropping in  parts  of  the  field. 
3.  Alternating     thick     clays     and 
water-bearing  sands. 
4.  Shirvanskaya     heavy-oil     zone, 
alternating   sands  and   clays, 
outcropping  in  parts  of  the 
field. 

Fish  remains. 

Upper  Oli- 
gocene. 

Middle 
Ol  i  g  o- 
cene. 

Foraminifera 
beds. 

5.  Light-oil  lenticles  in  the  hang- 
ing wall. 
3.  White    clays    and    marls,    with 
bituminous  streaks. 
7.  Green  marls. 

Globigerina 
and  Orbu- 
lina. 

°RAPPOPOBT,  F.  G. :  Discussion  of  CALDER'S  Paper.     Op.  tit.,  pp.  342-346. 

From  the  region  south  of  Maikop,  parallel  to  the  axis  of  the 
Caucasus,  petroliferous  strata  extend  northwestward  along  a  belt 
nearly  200  miles  long.  Many  of  the  rivers  in  this  region  carry  oil 
films  on  water. 

Taman  and  Kertch. — In  the  Crimean  district  oil  is  found  on  the 
Taman  and  Kertch  peninsulas,  at  the  south  side  of  the  Sea  of 
Azov.  On  the  Taman  peninsula  there  are  many  sharp  ridges  ris- 
ing frpm  swampy  plains.  The  tops  of  these  ridges  are  marked  by 
volcanoes  carrying  oily  mud.  The  Kertch  peninsula  is  made  up  of 
Oligocene  and  Miocene  beds1  forming  numerous  anticlines,  on 
which  mud  volcanoes  are  found.  The  structure  of  the  region  is 
shown  by  Fig.  232. 

Sviatoi. — Sviatoi  or  Holy  Island,  lies  in  the  Caspian  Sea  off 
REDWOOD,  BOVERTON:  A  Treatise  on  Petroleum,  vol.  1,  p.  150,  1913. 


544 


GEOLOGY  OF  PETROLEUM 


Apsheron  Peninsula,  about  30  miles  from  Baku.1  Practically  all 
of  the  island  except  the  center  and  small  patches  near  the  shore  is 
covered  with  beds  as  late  as  Pliocene.  These  beds  overlie  sand- 
stones, sands,  and  sandy  clays  of  Miocene  age,  which  crop  out  in 
the  center  of  the  island  and  form  an  asymmetric  dome  with  its 
long  axis  running  northwest.  On  the  northeast  flank  there  is 
much  faulting  in  the  Miocene  beds.  About  2,100  feet  or  more 
northeast  of  the  dome,  according  to  May,  the  oil-bearing  Miocene 
beds  rise  again,  forming  an  anticline.  Along  the  axis  of  the  main 
dome,  for  a  distance  of  about  a  mile,  there  are  10  or  12  mud  vol- 
canoes and  seeps,  most  of  which  occur  where  the  beds  are  faulted. 
The  soil  contains  enormous  deposits  of  pitch.  Parallel  to  the  zone 
of  mud  volcanoes  and  east  of  them  are  springs  of  salt  water,  and 


FIG.  232. — Map  of  the  Strait  of  Kertch,  Russia.  The  heavy  lines  indicate 
late  Tertiary  anticlines.  (After  Andrussov.  Redrawn  from  a  sketch  in  Suess 
Das  Antlitz  der  Erde,  vol.  3,  part  2,  p.  12.  The  original  is  not  accessible  to  me. 
W.H.E.) 

still  farther  east  is  a  bed  of  asphalt  covering  more  than  200,000 
square  yards.  Small  lakes  of  oil  are  forming  to-day.  From 
wells  drilled  southwest  of  the  anticline  water  spouted  above  the 
derrick.  The  oil,  all  of  which  comes  from  lower  Miocene  beds, 
has  a  specific  gravity  of  0.92  to  0.94. 

Cheleken  Island. — Cheleken  Island,  in  the  Caspian  Sea,  con- 
tains middle  Tertiary  strata  and  later  beds  correlated  with  the 
Baku  and  Apsheron  formations  of  the  Baku  region.  These  beds 
crop  out  on  an  anticline  which  is  extensively  faulted.  The  island 

XMAY,  H.:  Discussion  of  a  Paper  by  THOMPSON.  Inst.  Min.  and  Met. 
Trans.,  vol.  20,  p.  248,  1911. 


RUSSIA,  MESOPOTOMIA,  PERSIA  AND  EGYPT    545 

itself  is  a  structural  dome.  Hot  salt  springs  abound,  and  deposits 
of  ozokerite  are  found  in  faults.  Wells  on  this  island  have  been 
highly  productive.  Thompson1  states  as  probable  the  hypothesis 
that  the  highly  faulted  uplift  of  this  field  is  related  to  igneous 
bodies  concealed  below  the  surface.  Holland2  dissents  from 
Thompson's  view.  He  states  that  the  intense  faulting  present 
in  the  central  portion  or  axial  region  is  not  apparent  in  the  peri- 
pheral areas,  which  are  -occupied  by  the  later  beds.  This  differ- 
ence may  be  due  to  the  faulting  having  taken  place  prior  to  the 
deposition  of  the  later  beds,  but  as  there  is  no  pronounced  un- 
conformity between  the  two  series,  it  appears  probable  that  fault- 
ing was  originally  limited  to  the  central  part  of  the  dome.  The 
oil  is  in  part  of  paraffin  base  and  has  sealed  the  faults  by  forming 
ozokerite  in  them. 3 

Transcaspian  Province. — The  Mainland  east  of  the  Caspian 
Sea  also  yields  oil.  Napthnia  Gora,  or  Naptha  Hill,  is  about  100 
miles  inland  of  Krassnovodsk  and  16  miles  southwest  of  the 
Tageer  wells.  The  hill,  which  is  about  3  miles  long  by  about  a 
mile  and  a  half  wide,  appears  to  be  due  to  a  short  anticlinal  fold. 
Petroleum  mixed  with  sand  and  ozokerite  escapes  at  the  surface. 
Mud  volcanoes  throw  out  mud,  water,  petroleum,  and  ozokerite. 
It  is  said  that  fragments  and  even  layers  3  inches  thick  of  ozokerite 
have  been  found  in  the  mud  and  sand  hills  surrounding  these  vol- 
canoes. Abandoned  wells  on  the  northwestern  slope  show  where 
petroleum  was  collected  in  ancient  times.  Trial  borings  for 
petroleum  have  been  made  by  the  Government,  and  these,  at  a 
shallow  depth,  are  reported4  to  have  given  a  daily  output  of  500 
to  700  poods. 

Tiflis. — In  the  Tiflis  Government  petroleum  occurs  in  the  middle 
Jurassic  series  a  few  versts  southwest  of  Tsona,  on  the  Kutais 
border.  South  of  the  Kur,  about  16  or  20  miles  below  Gori,  the 
Sarmatian  limestones,  in  a  vertical  position,  contain  traces  of 
petroleum,  which  is  also  reported  to  occur  on  the  eastern  shore 
of  Lake  Toporovan,  southwest  Tiflis,  possibly  impregnating  some 
absorbent  igneous  rock.  East  of  Tiflis  the  Tertiary  belt  assumes 

THOMPSON,  A.  B.:  The  Relationship  of  Structure  and  Petrology  to  the 
Occurrence  of  Petroleum.  Inst.  Min.  and  Met.  Trans.,  vol.  20,  p.  230,  1911. 

'HOLLAND,  THOMAS:  Discussion  of  Paper  by  THOMPSON.     Op.  cit.,  p.  266. 

3I  have  no  data  concerning  the  geology  of  the  Emba  field  north  of  the  Cas- 
pian and  the  Derbeill  field  north  of  Baku.— W.H.E. 

^REDWOOD,  BOVERTON:  A  Treatise  on  Petroleum,  vol.  1,  pp.  14-15,  1913, 


546  GEOLOGY  OF  PETROLEUM 

a  more  regular  course  and  is  practically  continuous,  extending 
over  100  miles  southeastward.  Petroleum  is  produced  in  this  belt 
from  both  Oligocene  and  Miocene  beds.1 

Ferghana. — The  Ferghana  district,  about  400  miles  east  of 
Bokhara,  Turkestan,  produces  about  240,000  barrels  of  oil  a  year. 
Although  the  area  covered  by  the  oil  formation  is  very  large,  the 
results  of  drilling  are  said  to  be  discouraging.2 

Northern  Russia. — In  northern  Russia  about  400  miles  east- 
southeast  of  Archangel,  a  Government  boring  40  feet  deep  pene- 
trated blue  marl,  and  petroleum  flowed  in  a  continuous  stream  to 
a  height  14  inches  above  the  casing  of  the  well.3  A  second  well 
was  bored  with  similar  result.  Later  explorations  were  unsuc- 
cessful. The  oil  contains  41  per  cent  of  kerosene  and  is  superior 
to  the  Baku  oil. 

MESOPOTAMIA' 

The  oil  fields  of  Mesopotamia4  are  between  the  plateau  of  Iran 
and  the  Mesopotamian  depression,  north  of  latitude  30  N.,  in  the 
valleys  of  the  lower  Euphrates  and  Tigris  rivers.  They  lie  within 
the  Turkish  vilayets  of  Mosul,  Bagdad,  and  Busra.  The  oil- 
bearing  beds  extend  in  a  general  belt  striking  northwest  parallel 
to  a  line  of  Tertiary  folds  rising  on  its  eastern  border. 

The  oil  generally  occurs  in  Miocene  rocks,  which  consist  of 
bright-colored  sandstones,  marls,  and  limestones  permeated  with 
salt.  As  a  rule  the  petroleum  and  bitumen  are  found  in  soft  whit- 
ish limestones.  Sulphurous  springs,  some  of  them  hot,  saline 
springs,  oil  seeps,  gas  seeps,  and  asphaltic  deposits  are  numerous. 
These  bituminous  materials  have  been  utilized  for  centuries,  but 
there  is  no  considerable  oil  industry  in  Turkey. 

The  Chiarsukh  springs  occur  at  the  foot  of  the  Koh-i-Ahen- 
geran,  along  an  anticlinal  fold  which  fringes  the  Chiarsukh  River. 
Oil,  accompanied  by  brine  and  ozokerite,  flows  from  sandstone 
strata  underlying  marls.  A  small  native  industry  is  established.5 

REDWOOD,  BOVERTON:  Op.  tit.,  p.  152. 

'GOLUBIATUIKOFF;  D.  W.  I  A  Report  to  the  Russian  Geological  Committee, 
reviewed  by  Oil  and  Gas  Jour.,  vol.  16,  No.  1,  p.  36,  1917. 

'REDWOOD,  BOVERTON:  Op.  tit.,  p.  15. 

DOMINION,  LEON:  Fuel  in  Turkey.  Am.  Inst.  Min.  Eng.  Trans.,  vol.  56, 
pp.  237-256,  1916. 

^DOMINION,  LEON:  Loc.  tit. 


RUSSIA,  MESOPOTOMIA,  PERSIA  AND  EGYPT    547 
PERSIA 

Petroleum  seeps  and  asphalt  are  found  at  many  places  in  Persia. 
These  have  been  known  since  ancient  times.  Development  on  the 
modern  scale  began  in  1903,  and  a  few  years  later  at  Maidan-i- 
Naphtun,  near  Shustar,  a  well  1,100  feet  deep  came  in  and  oil 
spouted  70  feet  high,  carrying  away  the  derrick.  Since  then  oil 
concessions  covering  most  of  Persia  have  been  granted,  and  the 
Anglo-Persian  Oil  Co.  has  developed  an  extensive  field  which  is 
supplied  with  pipe  lines  and  a  refinery.  In  1919  it  was  said1 
that  wells  already  drilled  are  capable  of  producing  5,000,000  tons 
annually.  Many  of  the  wells  are  gushers  and  yield  heavily  by 
flowing. 

The  Persian  fields  are  closely  related  geologically  to  the  Baku 
field  of  Russia.  The  northern  field  borders  the  Caspian  Sea  and 
lies  southwest  of  Baku.  The  western  field  extends  from  Kerman- 
shah  southeastward  to  the  head  of  the  Persian  Gulf  and  thence 
continues  southeastward  on  the  border  of  the  gulf  to  the  Arabian 
Sea.  The  southern  field  lies  north  of  the  Arabian  Sea  along  the 
coast.  These  fields  are  shown  in  Fig.  233.  The  following  section 
after  Pilgrim  is  quoted  by  Hunter: 

GEOLOGIC  SECTION  OF  WEST  PERSIAN  OIL  FIELDS 

[Shelly  conglomerates  and  dead  coral  reef  of  littoral; 
Recent  and  sub-recent.  .  <     red  sand  hills  of  coast  of  Oman,  alluvium  of  Meso- 

{     potamia,  etc. 

Pleistocene Foraminiferal  oolite. 

Pliocene Bakhtiari  series,  grits  and  conglomerates. 

fFars  series,  marls,  clays,  and  sandstones  with  lime- 

\     stones  and  interbedded  strata  of  rock  gypsum. 

Miocene Urumieh  series,  limestones. 

Oligocene Nummulitic  limestone  of  Khamir. 

f  Nummulitic  limestone  of  Persia,  Muscat,  and  Bah- 

Eocene--' 1     rain  series. 

Upper  Cretaceous Hormuz  series,  lavas,  tuffs,  etc. 

In  the  field  near  Shustar  the  Fars  series  crops  out.  At  White 
Oil  Springs  seeps  yield  about  20  gallons  a  day  of  oil  resembling 

HUNTER,  C.  M. :  The  Oil  Fields  of  Persia.  Mining  and  Metallurgy,  No. 
158,  sec.  11,  pp.  1-8,  February,  1920. 


548 


GEOLOGY  OF  PETROLEUM 


kerosene.  There  are  two  strong  folds  in  this  region,  both  lying 
southwest  of  the  Iranian  Mountain  chain.  These  are  the  Maidan- 
i-Naphtun  fold  and  the  Ahwaz  fold,  36  miles  southwest  of  it.  The 
oil  in  the  Maidan-i-Naphtun  fold  is  found  in  the  Fars  formation 


£» 


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ft,     WOIAH 


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ARABIAN  $CA 


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—  PERSIA  — 


•     Reported  Oil  Shows 
'mnuiHv  Anglo-Persian  OH  Company^  Concession 
+  *  *  <-  Russo- Persian  Petroleum  Concession 

SCALC: 
Mifestoioo  too  too  Milts 


FIG.  233. — Sketch  map  showing  oil  fields  of  Persia.  (After  Hunter.) 

of  the  Miocene.  Oil  has  been  flowing  from  the  reservoir  under 
strong  pressure  for  10  years.  The  principal  productive  bed  is 
1,200  to  1,300  feet  deep  in  the  main  fields.  The  Ahwaz  anticline 
is  100  miles  long  and  strikes  west-northwest  through  Ahwaz.  Oil 


RUSSIA,  MESOPOTOMIA,  PERSIA  AND  EGYPT    549 


has  been  found  in  this  region  in  the  detrital  limestones  forming 
the  base  of  the  Fars  series.  This  anticline  is  the  farthest  outlying 
fold  of  the  Iranian  Mountain  chain  and  is  asymmetric,  having  a 
steep  vertical  or  inverted  dip  on  the  southwestern  face  and  a  gentle 
slope  on  the  northeastern  face.  In  the  neighborhood  of  Ahwaz 
the  crest  of  the  anticline  is  in  the  form  of  elongated  domes,  and 
denudation  has  shown  that  the  lowest  200  to  300  feet  of  exposed 
beds  belong  to  the  middle  group  of  the  Fars  series.  The  wells 
yield  considerable  gas.  Although  there  are  no  seeps  above  this 
fold,  the  bed  that  yields  the  seeps  at  White  Oil  Springs,  according 
to  Hunter,  is  supposed  to  be  present  at  no  great  depth. 

PROPERTIES  OF  PERSIAN  OILS'* 


Fractions 

Flash 

Spe- 

;  *; 

Point 

Lub- 

Location 

cine 
Grav- 

of 

Ben- 

Kero- 

ricat- 

Sulphur 

Odor 

Color 

Crude 

zine 

sene 

ing 

ity 

(°F.) 

(Per 

(Per 

Oils, 

cent) 

cent) 

(Per 

cent) 

Shustar  District. 

0.927 

27.0 

45 

Dark  green. 

White  Oil  Springs 

(Ahwaz)  

0.773 

Present. 

Inoffensive. 

Light  straw. 

Tchiah        Sourlch 

0.815 

Low. 

9.4 

57.6 

0.4  per  cent 

Inoffensive. 

Brown, 

(Near  Kasr-i- 

present. 

strongly 

Shirin). 

fluorescent. 

Daliki 

1.016 

170 

Present. 

Strongly    of 

Dark  brown. 

sulfuretted 

hydrogen. 

Qishm  

0.837 

190 

Pleasant. 

Brownish  red. 

"HUNTER,  C.  M.:  Op.  cit.,  p.  7. 


EGYPT 


The  oil  fields  in  Egypt  (Figs.  234,  235)  lie  along  the  west  coast 
of  the  Gulf  of  Suez,1  in  an  area  of  Cretaceous  and  Tertiary  strata. 
The  oil  is  found  in  Miocene  rocks2  and  also  in  the  Mesozoic. 

^UME,  W.  F. :  Some  Notes  on  the  Post-Eocene  and  Post-Miocene  Move- 
ments in  the  Oil-Field  Region  of  Egypt.  Geol.  Mag.,  decade  6,  vol.  4,  pp. 
5-9,  1917. 

2The  Oil  Fields  of  Egypt;  Abstract  from  Report  on  the  Oil-Fields  Region  of 
Egypt,  by  W.  F.  HUME,  Director  Geol.  Survey  of  Egypt,  with  a  geological 
map  (1:150,000)  from  surveys  by  JOHN  BALL,  23  plates  and  9  text  figures, 
Cairo,  Government  Press,  vol.  54,  pp.  315-320,  1917. 


550  GEOLOGY  OF  PETROLEUM 

As  stated  by  Hume,  a  basal  conglomerate  is  overlain  by  a  dark 
fossiliferous  limestone  (lower  middle  Miocene),  which  in  turn  is 
overlain  by  Globigcrina  marls.  These  beds  are  succeeded  by 


FIG.  234. — Sketch  map  of  region  of  Egyptian  oil  fields.  (After  Hume.) 


sw. 


RED  SEA 
HILLS  HILLS 


HE. 

JEBEL   7f/r  J£B£L  ARABA  SINAI  HILLS 

&    OulfofSuez__j^^rl^ 


E2  Oypsum^alf  series,  etc.-  EE3  Nubian  sandstone 

\±s^iEoc<?ne  li'mestone  IV/I  Granite 

I       \Cretaceous  beds  1»VJ  Schisfs,  ere. 
F'Fault 


FIG.  235. — Generalized  section  across  region  of  Egyptian  oil  fields.   (After 

Hume.) 

deposits  of  clay,  gypsum,  salt,  and  dolomitic  limestones.  Their 
total  thickness  is  from  3,000  to  6,000  feet.  Pliocene  and  Pleis- 
tocene strata  overlie  the  Miocene  beds. 


RUSSIA,  MESOPOTOMIA,  PERSIA  AND  EGYPT  551 


The  country  has  undergone  two  major  erogenic  movements, 
which  are  expressed  in  its  present  structure.  During  Cretaceous 
time,  in  a  great  depression,  limestones,  clays,  and  sandstones  were 


FIG.  236.— Sketch  map  of  Jebel  Zeit  oil  field,  Egypt.  (After  Hume.)  The 
Nubian  sandstone  is  Cretaceous.  The  coral  reef  is  Pleistocene. 

laid  down  on  an  old  foundation  of  granites  and  metamorphic  rocks. 
Emergence  and  erosion  followed.  This  was  succeeded  during  the 
Eocene  epoch  by  the  deposition  of  nummulitic  and  other  strata. 


552  GEOLOGY  OF  PETROLEUM 

At  the  end  of  Eocene  time  the  great  Egyptian  syncline  was  formed ; 
east  of  it  there  is  probably  a  corresponding  anticline.  A  number 
of  parallel  axes  were  developed  during  the  folding — one  running 
through  the  Red  Sea  Hills,  another  through  the  Sinai  Hills  of 
Arabia.  The  block  between  these  two  folds  was  faulted  down, 
and  during  middle  Miocene  time  beds  of  Globigerina  oozes  were 
laid  down  in  this  trough.  Upon  these  beds  a  series  at  least  3,000 
feet  thick,  consisting  of  limestone,  gypsum,  and  salt,  was  deposited. 
At  the  end  of  Miocene  time  the  region  again  became  subject  to 
compression,  which  resulted  in  the  formation  of  many  asymmetric 
folds  which  strike  northwest,  and  whose  more  steeply  inclined  sides 
lie  toward  the  Gulf  of  Suez.  The  ancient  petroleum  field  of  Jebel 
Zeit  is  shown  in  Fig.  236. 

At  Jemsa  and  Zeit  a  light  oil  was  found  in  Miocene  strata  below 
gypsum.  The  wells  at  Jemsa  went  to  salt  water  soon  after  they 
were  drilled. 

At  Hurgada  (Rorquada),  west  of  Gifatin  Island,  a  heavy  oil  is 
found  near  the  top  of  the  Nubian  (Cretaceous)  sandstone.  The 
structure  is  domatic. 


CHAPTER  XXVI 

BURMA  AND  OCEANICA 

BURMA 

Seeps  of  oil  are  found  at  many  places  in  Burma,  as  is  indicated 
by  Fig.  237.    The  chief  developments  are  located  along  the  Irra- 


FIG.  237. — Sketch  map  showing  location  of  oil  and  gas  occurrences  in  Burma. 

(After  Pascoe.) 

waddy  River,  where  the  oil  is  found  in  folded  and  faulted  Tertiary 
strata.   The  principal  fields  are  the  Yenangyaung  and  Yenangyat- 

553 


554 


GEOLOGY  OF  PETROLEUM 


Singu  fields.    Burma  furnishes  by  far  the  greater  part  of  the  oil 
produced  in  India,  as  is  shown  in  the  following  table. 

PETROLEUM  PRODUCED  IN  BURMA  AND  IN  INDIA,  1913-1917 


Year 

Burma 
(Imperial 
Gallons) 

Total,  India 

Quantity 

Value 

Imperial 
Gallons 

Barrels 
(42  United 
States 
Gallons) 

Rupees0 

Dollars 

1913      

272  ,865  ,397 
254  ,652  ,963 
282  ,291  ,932 
291  ,769  ,083 
272  ,795  ,191 

277  ,555  ,225 
259  ,342  ,710 
287  ,993  ,576 
297  ,189  ,787 
282  ,759  ,523 

7  ,930  ,149 
7  ,409  ,792 
8  ,202  ,674 
8  ,491  ,137 
8  ,078  ,843 

15  ,518  ,790 

14  ,378  ,475 
18  ,852  ,045 
16  ,791  ,075 
16  ,394  ,460 

5  ,035  ,803 
4  ,664  ,857 
6  ,116  ,232 
5  ,447  ,584 
5  ,318  ,909 

1914 

1915  
1916  
1917  

"The  value  of  the  rupee  is  taken  as  32.44}$  cents;  15  rupees  =£1. 

Yenangyaung. — The  Yenangyaung  oil  field1  is  on  an  elongated 
dome  whose  crest  lies  2  miles  east  of  the  Irrawady  River,  at  Yen- 
angyaung, in  the  Magwe  district.  Oil  seeps  have  long  been  known 
in  this  district,  and  in  the  period  before  modern  machinery  was 
introduced  the  Burmese  recovered  small  quantities  by  sinking 
shallow  shafts. 

The  country  is  a  rolling  plateau  about  600  feet  above  the  sea 
and  is  dissected  by  steep  ravines.  An  elliptical  area  of  Pegu  beds 
about  6  miles  long  and  1  mile  wide  is  surrounded  by  Irrawaddian 
sandstone  (Fig.  38,  p.  132).  The  Pegu  series  (Miocene)  consists 
principally  of  sand  and  clay,  with  some  calcareous  sandstones. 
Current  bedding  indicates  deposition  in  shallow  water.  Marine 
and  non-marine  fossils,  gypsum,  calcite,  and  carbonized  wood  are 
found  in  the  Pegu. 

The  Irrawaddian  series  (Pliocene),  which  locally  is  unconform- 
able  upon  the  Pegu,  consists  of  cross-bedded  loose,  friable  sands. 
Near  the  base  of  the  series  is  the  Red  bed,  a  persistent  member, 

^ASCOE,  E.  H.:  The  Oil  Fields  of  Burma.  India  Geol.  Survey  Mem.,  vol. 
40,  part  1,  pp.  55-100,  1912. 


BURMA  AND  OCEANICA 


555 


5  or  6  feet  thick,  which  contains  vertebrate  remains  and  is  used 
as  a  horizon  marker.  Pleistocene  and  Recent  sands  and  clays 
locally  cover  the  Irrawaddian. 

The  principal  structural  feature  of  the  field  (Fig.  238)  is  an 
elongated  dome  with  an  undulating  crest  studded  by  small  dip 
faults.  Both  the  Pegu  and  Irrawaddian  formations  are  cut  by 
dikes  of  mud  that  probably  represent  the  conduits  of  old  mud 
volcanoes  which  have  been  eroded. 

Most  of  the  producing  wells  are  scattered  over  an  elliptical  area 
of  between  1J4  and  lJ/£  square  miles  within  the  larger  elliptical 
area  of  the  dome.  The  larger  part  of  the  petroleum  has  come 
from  an  area  of  less  than  a  square  mile.  The  oil  sands  of  the  Pegu 
have  been  called  the  400-foot,  700-foot,  and  1,000-foot  sands,  but 
in  certain  areas  within  the  district  there  are  small  sand  pockets  of 
extremely  irregular  distribution. 


a,  Irrawaddian  beds;        b,  Pegu  beds; 
Horizontal  Scale  **  ¥ 


Vertical  Scale 


600 


1200 


c,  Oil  sands. 
34 1  mile 


2400  feet 


FIG.  238. — Section  through  Yenangyaung  oil  field,  Burma.  (After  Thompson.) 

Some  of  the  wells  in  the  Yenangyaung  field,  when  first  brought 
in,  spout  a  very  gassy  oil.  One  well  yielded  gas  at  first,  followed 
by  oil. 

The  Beme  area  of  this  district  at  the  surface  is  much  cut  by  mud 
dikes.  In  one  well  mud  rose  300  feet  in  the  casing. 

The  oil  and  gas  tend  to  rise  to  the  higher  structural  positions, 
but  there  is,  according  to  Pascoe,  no  clear  segregation  of  gas  above 
the  oil. 

Yenangyat-Singu.1 — The  Yenangyat  Hills,  a  long  range,  form 
the  right  bank  of  the  Irrawaddy  River  in  the  Pakokku  district. 
On  the  south  they  are  cut  through  obliquely  by  the  river,  and  their 

PASCOE,  E.  H. :  The  Oil  Fields  of  Burma.  India  Geol.  Survey  Mem.,  vol. 
40,  part  1,  pp.  101-123,  1912. 


556 


GEOLOGY  OF  PETROLEUM 


southern  continua- 
tions known  as  the 
Singu  Hills,  sink 
gradually  southward 
into  the  plateau.  The 
hills  consist  of  a  long 
inlier  of  Pegu  beds 
cropping  out  from  be- 
neath Irrawaddian 
sandstone,  as  at  Yen- 
angyaung.  The  struc- 
ture is  that  of  a  single 
asymmetric  anticlinal 
fold  (Figs.  239,  240), 
which  rises  at  three 
places,  producing  three 

e^  local  domes  or  crest 
maxima,  each  of  which 
forms  a  separate  oil 
field.  The  axis  is  not 

~^|   the  same   as  that  of 
••  Yenangyaung  but  lies 
on  a  line  about  8  miles 
east  of  it. 

As  in  the  Yenang- 
yaung district  the  Red 
bed  where  present  pro- 
vides a  horizon  marker. 
The  outcrop  of  the 
Pegu,  which  is  the  oil- 
bearing  series,  is  39 
miles  long  and  1J^  to 
3J/£  miles  wide.  On  ac- 
count of  the  steep  east- 
ward and  lower  west- 
ward dip  the  "crest 
locus,"  according  to 
Pascoe,  bends  strong- 
ly to  the  west.  Oil 
seeps  are  numerous. 


3    OJ 

£L- 


' 


BURMA  AND  OCEANICA 


557 


Ptgu 


The  most  valuable  part  of  this  anticline  is  the  Singu  area.  An 
oil  sand  is  exposed  on  the  north  side  of  Moksoma  Kon,  south  side 
of  Singu  area,  but  very  little  oil  has  been  obtained  there  (1912). 
A  well  in  this  vicinity  had  an  initial  yield  of  about  80  barrels  a 
day  from  a  depth  of  2,015  feet.  This  sand  is  identical  with  the  sand 
at  1,400  to  1,450  feet  near  the  crest  of  the  fold,  and  the  position 
of  the  oil-pool  boundary  has 
been  placed  a  little  to  the  <^ 

west  of  this  well.  According  ^  £ 

to  Pascoe,  this  sand  will 
probably  not  yield  oil 
enough  to  pay  where  the 
depth  is  greater  than  2,100 
feet.  No  wells  have  been 
drilled  east  of  the  crest  of 
the  anticline,  but  one  or  two 
situated  practically  on  the 
superficial  crest  have  struck 
small  supplies. 

On  the  local  domes  along 
the  anticline  oil  and  gas  are 
reached  at  depths  of  about 
1,400  to  2,000  feet,  the  gas 
rising  higher  on  the  struc- 
ture. There  are  ten  or  more 
sands,  which  split  or  join 
others,  making  correlation 
difficult.  The  principal  part 
of  the  production,  accord- 
ing to  Pascoe,  is  obtained 
above2,OOOfeet.Muchofthe 
oil  is  emulsified  with  water. 


Pegu 


Irrawadcfian 


R 


M 


Pegu 


FIG.  240. — Sections  through  Yenangya", 
oil  field,  Burma,  along  lines  shown  o  i 
Fig.  239. 

SUMATRA 


In  Sumatra  a  large  production  of  petroleum  is  obtained  from 
Miocene  and  Pliocene  sandstones  interbedded  with  shales  and 
clays.1  One  of  the  principal  Sumatra  fields  has  been  developed  on 

NOBLER,  A.:  Tijdschrift  van  het  Koninklijk  Nederlandsch  Aardrijks- 
kundig  Genootschap,  2d  ser.,  vol.  23,  No.  2,  p.  199,  1906. 

PRATT,  W.  E. :  Occurrence  of  Petroleum  in  the  Philippines.  Econ,  Geology, 
vol.  11,  p.  265,  1916, 


558  GEOLOGY  OF  PETROLEUM 

acute  anticlines.  Extensive  fields  exist  on  the  northeast  coast,  in  a 
belt  about  10  miles  wide,  extending  from  Edi,  in  Atjeh,  some  70 
miles  southeastward.  The  rock  strata  in  the  principal  Sumatra 
fields  consist  of  coarse-grained  loose  sandstones  and  marly  shales 
and  clays  of  Miocene  and  Pliocene  age.  These  beds  are  thrown 
into  folds,  and  the  oil  deposits  are  concentrated  in  anticlines. 
The  oil  has  an  unusually  high  proportion  of  the  more  volatile 
hydrocarbons,  evolving  inflammable  gas  in  the  cold.  Oil  is  reported 
in  the  kingdom  of  Siak,  and  an  oil  spring  was  noticed  in  the  Eocene 
conglomerates  3  or  4  miles  west  of  Kottabaru.  In  Palembang 
there  is  an  extensive  oil  field  in  rocks  of  upper  Tertiary  age,  from 
the  northern  margin  of  the  province,  100  miles  west  of  the  capital, 
to  the  vicinity  of  Lahat,  80  miles  to  the  south,  and  eastward  to 
the  Ogan  River.1 

In  1917,  at  Pangalan,  it  is  said  a  well  yielding  1,200  tons  of 
light-gravity  oil  daily  was  brought  in.  This  well  is  said  to  be  drilled 
on  a  large  anticlinal  fold. 

In  southern  Sumatra2  petroleum  is  found  only  in  the  Tertiary 
formations,  except  near  Bajur,  where  in  the  crater  of  the  Ringgit 
volcano,  according  to  Tobler,  oil  rises  from  schists.  The  richest 
oil  wells  have  been  struck  at  different  horizons  in  the  lower  Plio- 
cene, which  is  4,900  feet  thick  and  which  consists  in  this  region  of 
blue  clays  passing  locally  into  sandy  shales  and  argillaceous  fine- 
grained sandstones.  Calcareous  septaria,  which  are  absent  in  the 
upper  Pliocene,  are  characteristic  of  the  lower  division,  which  is 
also  extremely  rich  in  fossil  Mollusca.  Three  groups  of  brown  coal 
seams  are  characteristic  of  the  middle  Pliocene  division,  2,000  feet 
thick,  which  consists  of  blue  and  brown  clays,  shales,  and,  at  the 
top,  fine-grained,  soft  shaly  pale-blue  and  white  sandstones. 
Some  of  the  lignitic  seams  are  40  to  50  feet  thick,  and  some  con- 
tain slabs  of  silicified  coal  4  to  12  inches  thick.  Tobler  found  plant 
remains  in  the  middle  Pliocene,  but  practically  no  marine  fossils. 
Petroleum  occurs  in  this  division  also  in  workable  quantities  and 
appears  to  be  more  especially  concentrated  at  the  base  of  each  of 

REDWOOD,  BOVERTON:  A  Treatise  on  Petroleum,  vol.  1,  p.  161,  1913. 

THOMPSON,  A.  B. :  Oil-Field  Development,  p.  208,  1916. 

2ToBLER,  A. :  Einige  Notizen  zur  Geologic  von  Siidsumatra.  Naturforsch. 
Gesell.  Basel  Verh.,  vol.  20,  pp.  272-292,  1904.  Reviewed  in  Inst.  Min.  Eng. 
Trans,,  vol.  27,  pp.  701-702,  London,  1905,  The  original  paper  is  not  acces- 
sible to  me.— W.  H.  E. 


BURMA  AND  OCEAN  1C  A 


559 


the  brown-coal  groups.  The  topmost  coal  group  is  immediately 
overlain  by  the  vast  mass  of  the  tuffaceous  sediments  of  the  upper 
Pliocene,  3,300  to  5,000  feet  thick. 


PETROLEUM  PRODUCED  IN  DUTCH  EAST  INDIES,  1908-1917,  IN  METRIC  TONS 

(After  Northrop) 


Total 

Year 

Borneo 

Java 

Sumatra 

Metric 

Tons 

Barrels 

1908  

511  ,049 

137  ,013 

738  ,588 

1  ,386  ,650 

10  ,283  ,357 

1909  

411  ,506 

140  ,351 

922  ,894 

1  ,474  ,751 

11  ,041  ,852 

1910  

633  ,472 

142  ,503 

719  ,740 

1  ,495  ,715 

11,030,620 

1911    .    .  . 

814  ,707 

172  ,438 

683  ,523 

1  670  668 

12  172  949 

1912  

671  ,662 

184  ,989 

621  ,481 

1  ,478  ,132 

10  ,845  ,624 

1913  

797  ,059 

207  ,135 

529  ,947 

«1  ,534  ,223 

11,172,294 

1914 

C931  903 

226  590 

475  423 

bl  634  403 

11  834  492 

1915  

d960  ,896 

256  ,838 

491  ,611 

el  ,710  445 

12  386  800 

1916.  .    . 

n  ,047  462 

243  442 

526  080 

n  820  247 

13  174  399 

1917 

"946  ,737 

246  ,126 

583  ,384 

•1  ,778  ,495 

12  ,928  ,955 

"Includes  82  metric  tons  produced  in  Ceram. 
^Includes  487  metric  tons  produced  in  Ceram. 
clncludes  65,185  metric  tons  produced  in  British  Borneo, 
''includes  67,000  metric  tons  produced  in  British  Borneo. 
^Includes  1,100  metric  tons  produced  in  Ceram. 
'Includes  90,067  metric  tons  produced  in  British  Borneo. 
"Includes  3,263  metric  tons  produced  in  Ceram. 
AIncludes  77,614  metric  tons  produced  in  British  Borneo 
•Includes  2,248  metric  tons  produced  in  Ceram. 

1  gallon  Borneo  crude=7.5322  pounds. 
1  gallon  Java  crude=7. 1924  pounds. 
1  gallon  Sumatra  crude=6  7754  pounds. 

JAVA 

The  principal  oil  field  of  Java1  extends  from  Samarang  through 
Rembang  and  Surabaya  to  Madoera  Island  and  the  smaller 
islands  east  of  it.  Oil  is  found  10  kilometers  south  of  Surabaya,  in 
the  Lidah  and  other  pools.  In  the  residency  of  Rembang  are  the 
Tinawun  and  Panolan  pools.  The  most  productive  horizon  is 

'VERBEEK,  R.  D.  M.,  and  FENNEMA,  R.:  Geologische  Overzichtskaart  von 
Java  en  Madoera,  Geologische  Beschrijving  von  Java  en  Madoera  (no  date 
on  map). 


560 


GEOLOGY  OF  PETROLEUM 


near  the  contact  between  the  middle  and  upper  Miocene.  The 
depth  of  the  wells  ranges  from  500  to  800  feet.  The  average  pro- 
duction is  not  large  but  is  sustained.  The  crude  oil  has  a  density 
ranging  from  23°  to  40°  Baume,  and  contains  considerable  asphalt 
and  a  large  proportion  of  paraffin. 

The  anticlinal  structure  of  Madoera  Island,  shown  by  Fig.  241, 
is  typical.  The  rocks  are  Tertiary  clays,  sands,  and  marls. 

BORNEO 

The  island  of  Borneo  is  complicated  geologically  and  is  not 
fully  explored.  The  backbone  of  the  island  is  an  area  of 
crystalline  schists  with  which  are  associated  sandstones  and  lime- 
stones. Jurassic  fossils  have  been  found  in  some  of  the  sedi- 


Hcrfzonf-crf  Scale 
Vertical  Stale  exotggeroi-ecl  four  times 

FIG.  241. — Geologic  map  and  cross  sections  of  Madura  Island,  east  of  Java. 
(After  Verbeck  and  Fennema.) 

mentary  rocks.  These  rocks  are  much  disturbed  and  folded.  On 
them  are  deposited  Cretaceous  and  Tertiary  sediments,  the  latter 
predominating.  Eruptive  rocks  are  associated  with  the  Tertiary 
sediments. 

Petroleum  is  found  in  the  Tertiary  sedimentary  rocks.  Three 
fields  are  known.  One  of  them  is  at  Kutei  and  Balik  Papan  in 
southeast  Borneo,  where  a  company  associated  with  the  Dutch 
Shell  Company  operates  wells  and  refines  the  oil.  A  heavy  oil  is 
found  near  the  surface  in  wells  600  or  700  feet  deep.  Lighter  oils 


BURMA  AND  OCEAN  1C  A 


561 


are  found  at  depths  about  1,200  below  the  surface.  In  northeast 
Borneo,  on  Tarakan  Island,  and  on  the  mainland  opposite,  pro- 
ductive fields  are  developed.  In  Sarawak  also  fields  have  been 
developed  yielding  heavy  oil  like  that  of  Baku,  Russia. 

Very  little  is  available  to  me  regarding  the  relation  of  the  oil 
pools  to  the  geological  structure.  Stigand1  states  that  the  favor- 
able structural  feature  in  eastern  Borneo  is  a  long  anticline  with 
an  undulating  crest. 

PHILIPPINE  ISLANDS 

The  Philippine  Islands  form  an  archipelago  in  the  Malay  group, 
lying  between  Borneo  and  Formosa,  both  of  which  produce  oil. 
Seeps  and  residues  of  petroleum  and  inflammable  gas  are  found  at 
many  places  in  the  Philippines,  although  there  are  no  producing 
oil  wells.  In  the  Philippine  sedimentary  column  no  rocks  older 
than  the  Tertiary  have  been  identified  with  certainty.  The 
Oligocene,  which  carries  the  oldest  fossils  determined  in  the  islands, 
rests  unconformably  upon  a  complex  of  metamorphic  and  igneous 
rocks.  The  Tertiary  rocks  include  limestones,  shales,  muds,  sand- 
stones, and  tuffs.  The  Tertiary  section2  is  given  below. 

DIVISIONS  OF  THE  PHILIPPINE  TERTIARY     (After  Douville") 


Philippine  Islands 

Borneo 

Upper   limestone   with 
small  Lepidocyclinas. 

Lepidocydina  cf.  L.  Ver- 
beeki,  Miogypsina. 

Burdigalien. 

Sandstone  and  shale. 

Cycloclypeus  communis, 
Orbitolites,  Alveolinella, 
Miogypsina. 

Aquitanien. 

Miocene. 

Upper  Oligo- 
cene. 

Middle  limestone  with 
large  Lepidocyclinas. 

Lepidocydina  insulaenai- 
atalis,  L.  formosa,  L. 
richthofeni. 

Lower   limestone   with 
Nummulites. 
Coal  measures. 

Nummulites  niasi,  Amp- 
histegina  cf.  A.  niasi, 
Lepidocydina. 

Stampien. 

'STIGAND,  I.  A.:  Inst.  Min.  and  Met.  Trans.,  vol.  20,  p.  264,  London,  1911. 
2DouviLLE,  H. :  Sur  le  Tertiaire  des  Philippines.     Soc.  Ge*ol,  France  Butt.t 
4th  ser.;  vol.  9,  p.  338,  1909. 


562 


GEOLOGY  OF  PETROLEUM 


FIG.  242.— Geologic  map  of  the  Philippine  Islands.  (After  Smith,  with  addi- 
tions by  W.  H.  E.) 


BURMA  AND  OCEANICA 


563 


LE.GENO 

Active  ordormant  volcanoes 
Extinct  or  solfafaric  volcanoes 

Tectonic     lines 
a    inner  series  of  Becker 


FIG.  243 — Map  showing   tectonic  lines  and  volcanic  centers  of  Philippine 
Islands.     (After  Smith.) 


564  GEOLOGY  OF  PETROLEUM 

The  petroleum-bearing  beds  are  generally  folded  so  that  they 
dip  at  high  angles.  The  shale  series  is  closely  folded,  but  the  over- 
lying rocks  usually  dip  more  gently,  though  in  the  same  direction. 
The  difference  in  dip  is  evidence  of  unconformity  between  the 
shale  series  and  the  overlying  rocks.  The  folds  into  which  the 
beds  are  thrown  are  characterized  by  sharp  broken  anticlines  and 
by  broader,  less  acute  synclines.1 

Fig.  242  is  a  geologic  map,  after  Smith,2  on  which  are  plotted 
localities  where  oil  residues  occur,  taken  from  a  map  by  Pratt. 
Fig.  243  shows  the  principal  tectonic  lines. 

At  Villaba,  near  the  northwest  end  of  Leyte,  petroleum  residues 
are  found  in  considerable  amounts.  The  largest  deposit  is  in  a 
mass  of  porous  limestone  and  sandstone  having  an  outcrop  200 
feet  long  and  30  feet  high.  The  rock  is  impregnated  for  at  least 
30  feet  from  the  exposed  face.  Solid  residues  of  black  petroliferous 
material  fill  fissures  several  feet  wide.  Oil  seeps  are  numerous, 
yielding  brown  petroleum  having  a  gravity  of  28°  to  30°  Baume. 
The  rocks  are  of  upper  Tertiary  age,  and  the  field  lies  near  one  of 
the  principal  tectonic  lines.  The  beds  are  thrown  into  folds  and 
are  faulted,  and  the  principal  seeps  lie  along  an  escarpment  that  is 
probably  a  fault  line. 

In  the  southern  part  of  the  peninsular  portion  of  Tayabas, 
which  juts  off  the  southern  coast  of  Luzon,  in  line  with  the  axis 
of  the  eastern  cordillera,  there  are  four  small  petroleum  seeps  and 
half  a  dozen  other  places  where  traces  of  petroleum  and  inflam- 
mable gas  are  found.  These  showings  are  distributed  over  an  area 
25  miles  long  by  12  miles  wide.  The  rocks  are  Tertiary  and  have 
the  structure  of  an  anticlinorium  that  includes  steeply  dipping 
asymmetric  anticlines.  Erosion  has  taken  place  more  rapidly 
along  the  broken  crests  of  the  sharp  anticlines,  and  valleys  mark 
the  anticlinal  axes.  The  result  is  that,  although  the  peninsula  has 
a  general  anticlinal  structure,  the  highest  elevations  and  the  bulk 
of  the  land  mass  are  within  the  synclines.  Traces  of  petroleum 
are  found  wherever  the  massive  shale  beds  of  the  upper  part  of  the 
shale  series  are  exposed,  and  the  principal  seeps  of  petroleum  occur 
where  erosion  has  uncovered  these  beds  on  the  crests  of  sharp 


,  W.  E.  :  Occurrence  of  Petroleum  in  the  Philippines.     Econ.  Geology, 
vol.  11,  pp.  246-265,  1916. 

2SMiTH,  W.  D.  :  The  Philippine  Islands,  included  in  a  separate  of  the  Hand- 
buch  der  Regionalen  Geologic,  p.  4,  Heidelberg,  1912. 


BURMA  AND  OCEANICA  565 

folds.  The  shale  from  which  the  petroleum  escapes  emits  an  odor 
of  light  oil.  It  contains  numerous  small  calcareous  shells  of 
Globigerina,  some  of  which  are  greasy.  Gas  usually  accompanies 
the  petroleum,  bubbling  up  through  the  water,  and  a  spring  of 
salt  water  occurs  near  the  southernmost  seep  on  the  eastern  anti- 
cline, at  an  elevation  of  several  hundred  feet.  At  the  central 
seep  two  wells,  117  and  300  feet  in  depth,  have  been  drilled  on  an 
anticline.  The  shallower  well,  which  is  only  3  inches  in  diameter 
and  was  drilled  by  hand,  encountered  small  quantities  of  petroleum 
and  inflammable  gas.  Possibly  a  barrel  of  oil  a  day  couhl  be 
obtained  from  this  hole.  The  other  well  obtained  a  temporarily 
strong  flow  of  inflammable  gas.1 

In  Pangasinan,  west-central  Luzon,  a  well  drilled  by  the  Bureau 
of  Public  Works  encountered  salt  water  and  a  little  petroleum  in 
organic  clay  or  mud  at  a  depth  of  1,200  feet.  The  outcropping 
rocks  are  limestones,  calcareous  sandstones,  and  marls  of  upper 
Tertiary  age.  Structurally  the  area  is  a  gentle  monocline,  dipping 
west. 

In  Panay  a  well  was  drilled  for  artesian  water  at  the  town  of 
Janiuay,  2  miles  east  of  the  southern  gas  seep,  and  at  a  depth  of 
1,800  feet  this  well  encountered  salt  water,  charged  with  gas. 
Both  gas  and  water  have  flowed  by  heads  through  a  period  of  two 
years,  the  well  having  been  abandoned,  and  tiny  films  of  oil  appear 
on  the  surface  of  the  water.  The  well  is  in  an  alluvium-filled 
structural  valley.2 

Petroleum  is  found  in  shale  near  the  towns  of  Toledo  and 
Alegria,  35  miles  apart,  on  the  western  coast  of  Cebu.  The  wells 
at  Toledo  and  the  adjacent  seep  are  upon  the  outcrop  of  sandy 
bedded  shales  which  dip  northwest  at  angles  of  45°  or  more  and 
form  a  monocline  flanking  the  cordillera  of  Cebu.  The  petroleum 
at  Alegria  comes  from  steeply  dipping  beds  of  sandy  blue  shale  in 
the  crest  of  a  sharp  anticline  that  parallels  the  adjacent  coast. 
Two  miles  to  the  south  of  the  seep,  and  along  the  line  of  the  anti- 
clinal axis,  there  is  a  spring  of  hot  water.3 


,  W.  E.:  Op.  ciL,  p.  253. 
TRAIT,  W.  E  :  Op.  cit.,  p.  256. 
3PRATT,  W.  E.:  Op.  cit.,  pp.  256-257. 


566 


GEOLOGY  OF  PETROLEUM 


JAPAN  AND  FORMOSA 

The  chief  oil  districts  in  Japan1  are  in  the  provinces  of  Echigo, 
Shinano,  Akita,  Totomi,  and  Hokkaido,  and  one  is  in  Formosa.  In 
each  of  these  districts  there  are  one  or  more  oil  fields.  The  oil  in 
Japan  is  associated  everywhere  with  Tertiary  sedimentary  rocks 
and  is  found  in  anticlinal  folds. 

The  early  methods  of  getting  the  oil  were  simple.  Where  seeps 
occurred,  as  at  Kurokawe,  in  the  Niitsu  field  in  Echigo,  trenches 
or  shallow  wells  were  dug  and  allowed  to  fill  with  oil.  The  Nippon 
Petroleum  Co.  in  the  fall  of  1890  set  up  a  drill  over  an  old  dug  well. 
A  well  1,000  feet  deep  was  completed  in  April,  1892,  and  began 
with  a  production  of  45  barrels  a  day  of  oil  of  42°  Baume.  Other 
productive  wells  were  drilled  in  succession  to  a  depth  of  1,500  feet. 
The  first  gusher  was  struck  at  Amaze,  in  the  Nishiyama  field, 
Echigo  district. 

PETROLEUM  PRODUCED  IN  JAPAN  AND  FORMOSA,  1913-1917,  IN  KOKU" 
(From  the  Department  of  Agriculture  and  Commerce,  Tokyo) 


Field 

1913 

1914 

1915 

1916 

1917 

Akita   .  . 

76  ,830 
4,218 
1  ,610  ,117 
1,983 
336 
98 

625  ,719 
6,270 
1  ,761  ,792 
2,055 

989  ,223 

8,846 
1  ,728  ,687 
1  ,720 

879  ,188 
6,627 
1  ,733  ,934 
1,646 

874  ,484 
5,763 
1  ,655  ,250 
1,551 

Hokkaido  
Niigata6  
Shizuoka  

Yamagata 

Others   

Formosa  

1  ,693  ,582 
15  ,933 

2  ,395  ,836 
14  ,708 

2  ,728  ,476 
16  ,651 

2  ,621  ,395 
16  ,966 

2  ,537  ,048 
12  ,340 

Grand  total  

1  ,709  ,515 

2  ,410  ,544 

2  ,745  ,127 

2  ,638  ,361 

2  ,549  ,388 

al  koku==39.7  English  gallons=47.46  United  States  gallons=1.136  United  States  barrels. 
b  Includes  the  oil  from  Nishiyama. 

The  Echigo  and  Akita  districts  produce  90  per  cent  of  the  oil  of 
Japan.  The  Tertiary  petroliferous  beds,  according  to  Iki,2  con- 

^LEMENTS,  J.  M.:  Petroleum  in  Japan.  Econ.  Geology,  vol.  13,  pp.  512- 
523,  1918. 

2lKi,  T. :  Preliminary  Note  on  the  Geology  of  Echigo  Oil  Field.  Geol.  Soc. 
Japan,  Mem.,  No.  2,  pp.  29-57,  Tokyo,  1910. 


BURMA  AND  OCEANICA  567 

PETROLEUM  PRODUCED  IN  JAPAN  AND  FORMOSA,  1908-1917 


Year 

Japan 

Formosa 

Total 

1908 

Koku 
1  ,815  ,001 

1  ,657  ,036 
1  ,520  ,458 
1  ,529  ,593 
1  ,458  ,290 
1  ,693  ,582 
2  ,395  ,836 
2  ,728  ,476 
2  ,621  ,395 
2  ,537  ,048 

Barrels 
2  ,061  ,841 
1  ,882  ,393 
1  ,727  ,240 
1  ,737  ,618 
1  ,656  ,617 
1  ,923  ,909 
2  ,721  ,670 
3  ,099  ,549 
2  ,977  ,905 
2  ,884  ,624 

Koku 
7,310 

5,664 
3,208 
1,442 
3,040 
15  ,933 
14  ,708 
16  ,651 
16  ,966 
12  ,340 

Barrels 
8,304 

7,170 
4,062 
1,638 
3,454 
18,100 
16  ,708 
18  ,915 
19  ,273 
14  ,030 

Koku 
1  ,822  ,311 
1  ,662  ,700 
1  ,523  ,664 
1  ,531  ,035 
1  ,461  ,330 
1  ,709  ,515 
2  ,410  ,544 
2  ,745  ,127 
2  ,638  ,361 
2  ,549  ,388 

Barrels 
2  ,070  ,145 

1  ,889  ,563 
1  ,730  ,882 
1  ,739  ,256 
1  ,660  ,071 
1  ,942  ,009 
2  ,738  ,378 
3,118,464 
2  ,997  ,178 
2  ,898  ,654 

1909.       ..;... 

1910.  .  .  ,  
1911  

1912  
1913  
1914      .  . 

1915 

1916  

1917 

sist  of  sandstones  and  volcanic  tuffs  interbedded  with  shales.  The 
oil-bearing  areas  are  broken  into  a  series  of  small  mountain  ridges, 
of  which  the  highest  rises  to  an  altitude  of  2,300  feet,  although  the 
general  height  is  much  lower.  The  ridges  normally  correspond 
to  anticlines  and  strike  northeast;  the  valleys  occupy  synclines. 
Broadly  the  oil  fields  correspond  with  these  anticlines.  In  the 
Echigo  and  Akita  districts  oil  occurs  at  three  horizons.  The  beds 
at  the  upper  horizon  consist  of  shale,  sandstone,  and  conglomerate, 
and  those  at  the  middle  one  of  shale  with  thin  beds  of  sandstone. 
The  lower  oil  zone  is  subdivided  into  two  parts — an  upper  one  of 
sandstone  and  shale  and  a  lower  one  of  shale,  sandstone,  and  tuff. 
The  most  productive  oil  strata  are  in  the  middle  and  lower  zones. 
The  sandstone  and  tuff  are  the  chief  oil  carriers,  though  some  oil 
is  obtained  in  places  from  the  shale.  Volcanic  rocks,  tuffs,  and 
dikes  are  found  with  the  Tertiary  oil  strata,  some  contemporaneous 
with  and  others  intrusive  in  the  sediments.  Where  the  oil  strata 
are  cut  by  an  intrusion  the  oil  is  reported  to  be  of  low  specific 
gravity,  much  of  it  averaging  even  less  than  10°  Baume.  As  a 
rule  the  heavy  oils,  according  to  Clements,  occur  at  the  highest 
horizon. 

The  Nishiyama  field1  is  the  most  productive  one  in  the  Echigo 
district.  The  axis  of  the  Nishiyama  anticline  strikes  N.  45°  E., 
and  along  the  axis  the  northwest  side  of  the  anticline  is  dropped 
down  by  faulting.  The  shallow  wells  are  along  the  southeast  side 

^Production  included  above  in  Niigata,  9. 


568 


GEOLOGY  OF  PETROLEUM 


of  the  anticline.  Those  so  f.ar  developed  range  in  depth  from 
1,490  to  1,790  feet.  The  deeper  wells  are  on  the  northwest  side 
of  the  anticline.  Their  average  depth  is  2,980  feet,  but  one  reached 
a  depth  of  4,613  feet. 

The  only  field  in  which  gas  is  produced  in  notable  quantity  is 
the  Nishiyama  field,  in  the  Echigo  district.  One  company  pro- 
duces from  this  field  4,000,000  cubic  feet  of  gas  a  day. 

Oil  seeps  are  numerous  in  the  Washinoki  region,  Hokkaido.  A 
section  made  by  B.  S.  Lyman  in  1875  is  shown  as  Fig.  244. 


•'-      §•    36^^  -S- 

<*t     *    ill  1 

§  a=*§  a 

a-    jg-so.  s- 

SJ. 


-     ^ 

Sj-  ^5 


0;  a 

?l 


o  too          soo 


Scale 

FIG.  244. — Geologic    section    of   Washinoki    oil    region,    Hokkaido,    Japan. 

(After  Lyman.} 

Formosa  (Taiwan),  immediately  north  of  the  Philippine  Islands 
and  geologically  similar  to  them,  produces  a  little  petroleum  from 
Miocene  shales  and  sandstones.1 

CHINA 

Oil  is  found  in  Szuchuan  where2  there  are  in  the  neighborhood 
of  Fu-chuan  wells  from  1,000  to  3,500  feet  deep,  in  which  petro- 
leum occurs  with  gas  and  brine.  The  gas  is  used  in  evaporating 
the  brine  and  the  petroleum  is  burned  in  lamps  without  refining. 

NEW  ZEALAND 

Petroleum1  is  found  near  New  Plymouth,  Paritutu,  Taranaki, 
North  Island,  New  Zealand,  on  the  north  slope  of  Mount  Egmont. 

IPRA.TT,  W.  E. :  Occurrence  of  Petroleum  in  the  Philippines.  Econ.  Geology, 
vol.  11,  p.  265,  1916. 

2CoLDRE,  Louis:  Les  Salines  et  les  Puits  de  Feu  de  la  province  du  Se-Tchoan, 
Annales  des  Mines,  Ser.  8,  vol.  xix,  p.  441  (1891). 


BURMA  AND  OCEAN  1C  A  569 

The  production  is  small.  Oil  seeps  are  found  along  the  coast  near 
the  breakwater  at  New  Plymouth,  where  on  calm  days  the  sea 
locally  is  often  covered  with  an  oil  film.  Gas  seeps  are  numerous, 
and  a  mud  volcano  is  reported  to  have  erupted  violently  in  1859. 
Oil  is  found  in  the  Onairo  series  (Miocene),  which  consists  of  sand- 
stones, conglomerates,  clays,  and  limestones,  with  some  coal  seams. 
It  is  overlain  unconformably  by  the  Pouakai  series,  but  it  seems 
probable  that  no  great  lapse  of  time  separates  the  two  series  and 
that  in  some  places  they  are  conformable.  If  inclined  the  Pouakai 
beds  should  form  a  key  to  the  inclination  of  the  Onairo  series. 
The  Pouakai  beds,  however,  are,  according  to  Clark,  nearly  every- 
where horizontal.  In  the  more  eastern  portion  of  the  subdivision 
there  is  evidence  that  the  Onairo  rocks  form  the  western  end  of  an 
eastward-pitching  anticlinorium,  whose  axis  runs  in  an  east-south- 
east direction  through  the  southern  portion  of  the  Waitara district.2 
Salt  water  is  associated  with  the  oil.  It  is  more  concentrated 
than  sea  water  and  consists  principally  of  sodium  chloride  and  is 
nearly  free  from  sulphate.  It  carries  20  parts  in  a  million  of 
sodium  iodide.  The  gases  contain  methane,  ethane,  and  olefins, 
and  some  are  nearly  half  carbon  dioxide  and  nitrogen. 

AUSTRALIA 

At  Roma,3  Queensland,  Australia,  about  275  miles  west  of  Bris- 
bane, inflammable  gas  was  discovered  in  1904  in  a  deep  boring 
sunk  for  water.  The  gas-bearing  strata  are  probably  the  Walloon 
series,  of  Jura-Trias  (?)  age.  They  consist  of  sandstones,  dark 
shales,  and  thin  seams  of  coal,  and  both  vertical  and  lateral  changes 
are  closely  spaced.  The  gas-bearing  stratum  is  said  to  be  a  gray 
shale. 

The  structure  is  monoclinal,  and  the  dip  is  about  150  or  200  feet 
to  the  mile.  The  beds  are  but  little  disturbed.  The  gas  is  said 
to  be  mainly  methane,  but  contains  no  gasoline.  The  pressure  is 
low.  No  salt  water  is  reported. 

There  are  no  surface  indications  of  gas  or  oil.  The  gas  belt  is 
1,500  feet  below  the  lowest  of  the  coal  seams  and  about  3,700  feet 

^LARK,  E.  DE  C. :  The  Geology  of  the  New  Plymouth  Subdivision,  Tara- 
naki  Division.  New  Zealand  Geol.  Survey  Bull.  14,  new  ser.,  pp.  1-47,  1912. 

2Idem,  p.  38. 

'CAMERON,  W.  E. :  Report  on  the  Significance  of  a  Flow  of  Gas  in  the  Roma 
No.  2  Bore.  Queensland  Geol.  Survey  Pub.  247,  1915. 


570  GEOLOGY  OF  PETROLEUM 

below  the  surface.  In  the  first  well  drilled  the  gas  was  allowed  to 
escape  for  four  years;  it  was  then  shut  off  and  gaged  and  found  to 
flow  at  the  rate  of  about  70,000  feet  a  day.  The  flow  decreased 
rapidly  afterward.  In  1907  a  second  deep  well  was  sunk  about 
250  feet  south  of  the  first  gas  well.  It  struck  a  heavy  flow  of  gas 
that  lighted  from  the  boilers  and  burned  46  days. 


CHAPTER  XXVII 

CARIBBEAN  ISLANDS 
CUBA 

Asphalt,  pitch,  and  oil  seeps  have  been  known  in  Cuba1  for 
many  years,  but  little  petroleum  has  been  recovered. 

The  rocks  of  Cuba  may  be  divided  into  five  series,  as  follows: 

5.  Quaternary  and  Recent  deposits,  including  coral  limestones, 
terrace  gravels,  soils,  and  sands. 

4.  Tertiary  rocks,  igneous,  in  part. 

3.  Upper  Cretaceous  marls,  shales,  sandstones,  conglomerates 
and  some  limestone. 


Sfrcr/ts  of  Flo  riolct 
Harva 


CHI  Quaternary 

CZH  Edrrly  Terfiary 

ESS  Upper  Crefaceous 

[y^j\  Trictssic  and  Jurassic 

i+  +  i  Pps>  1~-  Paleozoic  igneous  rocks 

b'~'\  Metamorpbic  rocks 


FIG.  245. — Geological  sketch  map  of  Cuba. 

2.  Triassio  and  Jurassic  limestones  and  associated  rocks. 

1.  The  basement  complex,  consisting  of  granites,  schists,  slates, 
and  limestones.  Of  unknown  age,  most  of  them  probably  Pale- 
ozoic or  older.  Includes  probably  also  some  serpentines  of  Cre- 

^EGOLYER,  E. :  The  Geology  of  Cuban  Petroleum  Deposits.  Am.  Assoc. 
Petroleum  Geologists  Bull,  vol.  .2,  pp.  133-167,  1917. 

VAUGHAN,  T.  W. :  Bitumen  in  Cuba.  Eng.  and  Min.  Jour.,  vol.  73,  p. 
344,  1902. 

HAYES,  C.  W.,  VAUGHAN,  T.  W.,  and  SPENCER,  A.  C.:  Report  on  a  Geo- 
logical Reconnaissance  of  Cuba,  made  under  the  direction  of  GEN.  LEONARD 
WOOD,  Military  Governor,  123  pp.,  17  figures  and  maps,  Washington,  1901. 
Chapter  on  asphalt  and  petroleum  same  as  VAUGHAN'S  work  cited  above. 

PECKHAM,  H.  E. :  Bituminous  Deposits  of  Cuba.  Am.  Jour.  Sci.t  4th  ser., 
vol.  12,  pp,  33-41,  1901. 

571 


572  GEOLOGY  OF  PETROLEUM 

taceous  age.     Serpentine  is  said  to  crop  out  in  every  province 
in  Cuba. 

The  basement  rocks  and  the  Triassic  rocks  are  in  general  in- 
tensely folded  and  are  overlain  by  the  Cretaceous  and  later  rocks, 
which  as  a  rule  have  comparatively  low  dips.  The  Cretaceous 
and  older  rocks  are  intruded  by  igneous  rocks.  The  Quaternary 
and  Recent  deposits  are  laid  down  upon  the  older  rocks  and  are 
now  forming  near  the  sea  shore. 

The  structure  in  general  is  anticlinal,  the  older  rocks  forming 
the  central  axis  and  younger  rocks  cropping  out  on  either  side. 
The  folding  was  probably  accomplished  in  the  Tertiary  or  in  a 
later  period.  Subordinate  folds  occur  away  from  the  central  axis. 

Asphalt,  oil  seeps,  and  gas  seeps  have  been  reported  from  every 
province  in  Cuba  and  extend  over  a  distance  of  475  miles.  They 
are  most  common  on  the  north  coast,  in  a  zone  some  20  miles  wide 
between  Esperanza  and  the  eastern  boundary  of  Santa  Clara  prov- 
ince. The  scattered  wells  that  have  been  drilled  here  have  not 
yielded  commercial  supplies,  though  several  of  them  have  encoun- 
tered oil  or  gas.  Most  of  the  occurrences  are  in  fractured  serpen- 
tines. De  Golyer1  believes  that  the  oil  was  derived  from  the 
Jurassic  limestones  or  other  sedimentary  rocks,  that  the  igneous 
rocks  from  which  the  serpentines  are  derived  were  intruded,  for 
the  most  part,  into  the  Cretaceous  rocks  that  overlie  the  Jurassic, 
and  that  the  asphalt  deposits  and  oil  seeps  found  in  the  serpentine 
and  other  igneous  rocks  are  the  result  of  oil  seeping  from  the  under- 
lying sedimentary  rocks  or  from  patches  of  the  sedimentary  rocks 
which  have  been  caught  up  in  the  serpentine.  It  is.  believed  by 
some,  however,  that  the  Cretaceous  beds  are  unconformable  with 
some  of  the  serpentine  bodies  and  that  the  oil  has  accumulated 
near  the  unconformity. 

The  oil  recovered  is  of  a  remarkably  high  grade,  ranging  from 
55°  to  70°  Baume.  One  well,  which  belongs  to  the  Cuban- Ameri- 
can Sugar  Co.,  is  at  Motembo,  in  the  Province  of  Santa  Clara.  It 
is  about  1,900  feet  deep,  and  yields  10  gallons  of  70°  Baume  oil 
daily.  Other  wells  from  300  to  700  feet  deep  have  been  drilled  in 
the  same  region.  The  most  that  has  so  far  been  taken  from  a 
single  well  (Cardenas)  does  not  exceed  100,000  gallons. 

Several  wells  have  been  sunk  both  east  and  west  of  Cardenas, 
attaining  depths  of  1,000  to  2,385  feet,  the  latter  the  maximum 

I0p.  tit.,  p.  165. 


CARIBBEAN  ISLANDS 


573 


depth  for  the  island.  They  have  all  started  in  limestone 
and  finished  in  serpentine.1  Commercial  production  was  not 
obtained  in  any  of  the  wells. 

HAITI  AND  SANTO  DOMINGO 
On  the  island  of  Haiti  indications  of  oil  have  been  noted  3  miles 


H 


orcxl  limestone 
fc£v]  Cce&nic  deposits 

Scotland  series 
Fault 


Scale 


FIG.  246. — Geologic  map  of  Barbados  Island.  (After  Harrison  and  Jukes- 
Browne.) 

north  of  Axua  and  on  the  coast  near  San  Cristobal,  10  or  15  miles 
west  of  Santo  Domingo.     The  oil  is  said  to  be  derived  from  Cre- 
1  ARNOLD,  RALPH  :  Conservation  of  the  Oil  and  Gas  Resources  of  the  Amer- 
icas.    Econ.  Geology,  vol.  11,  pp.  301-302,  1916. 


574  GEOLOGY  OF  PETROLEUM 

taceous  beds.1     A  well  at  Azua  is  reported  to  have  flowed  com- 
mercial quantities  of  20°  Baume  high-sulphur  oil. 

BARBADOS 

Oil  is  found  on  the  east  side  of  Barbados  Island,2  in  Miocene3 
sandstones  and  shales  known  as  the  Scotland  series  (Fig.  246). 
Manjak,  a  tar  formed  by  the  drying  of  oil,  has  been  exploited. 
The  production  of  oil  is  small  and  has  been  obtained  from  shallow 
wells.  There  is  a  well  \Y^  miles  north  of  St.  Andrew,  and  another 
one  about  3  miles  southwest.  South  of  that  point  is  Tarry  Gully, 
which  derives  its  name  from  earth  saturated  with  petroleum. 

The  rocks  in  the  Scotland  district,  which  includes  the  parishes 
of  St.  Joseph  and  St.  Andrew,  consist  of  thick-bedded  sandstones, 
coarse  grits,  bituminous  sandstones  and  shales,  and  dark-gray  and 
mottled  clays.  The  strata  are  much  disturbed  and  are  broken  by 
many  faults.  In  many  places  the  oil  is  found  in  pools  on  the  fields, 
and  in  a  little  valley  about  1,000  yards  east  of  the  Lloyd  wells,  at 
St.  Andrew,  the  oil  trickles  out  along  the  foot  of  a  hill.  In  this 
district  there  is  also  the  "boiling  spring,"  where  in  a  pool  of  water 
inflammable  gas  bubbles.  The  Lloyd  wells  formerly  numbered 
21,  but  in  1895  there  were  only  5.  These  wells  were  dug  5  feet  in 
diameter  and  from  80  to  140  feet  deep,  and  were  lined  with  pine 
wood.  All  yielded  oil,  and  1  or  2  barrels  could  be  obtained  daily 
from  each  well. 

TRINIDAD 

Trinidad4  is  an  island  in  the  Caribbean  Sea  off  the  coast  of 
Venezuela.  Trinidad  is  famous  for  its  asphalt  lake,  which  has 
been  well  known  for  centuries  and  from  which  asphalt  has  been 
recovered  extensively  and  exported.  Lately  it  has  produced  con- 
siderable oil,  mostly  of  low  grade.  The  oil  ranges  in  density  from 
14°  to  25°  Baume  and  is  essentially  a  fuel  oil.  Recently  some 
higher-grade  oils  have  been  discovered.  These  yield  gasoline  and 
kerosene  and  are  refined  in  distilleries  on  the  island. 

ARNOLD,  RALPH:  Op.  cit.,  p.  302. 

REDWOOD,  BOVERTON:  A  Treatise  on  Petroleum,  vol.  1,  p.  192,  1913. 

'RALPH  ARNOLD  states  that  the  Scotland  series  is  Oligocene.  Econ.  Geol , 
vol.  00. 

4WALL,  G.  P.,  and  SAWKINS,  J.  G.:  Report  on  the  Geology  of  Trinidad- 
West  Indian  Survey,  part  1,  pp.  1-211,  1860. 


CARIBBEAN  ISLANDS 


575 


The  northern  part  of  Trinidad  (Fig.  247)  is  made  up  of  meta- 
morphic  rocks.  The  central  and  southern  parts  consist  of  Cre- 
taceous, Tertiary,  and  Quaternary  sediments.  The  Tertiary  and 
older  rocks  are  thrown  into  folds,  some  of  which  are  asymmetric 
and  overturned.  Exudations  of  oil  and  asphalt,1  oil  seeps,  gas 
seeps,  and  mud  volcanoes  are  present  on  a  grand  scale,  many  of 
them  on  crests  of  anticlines.  Cunningham-Craig2  says  that  it  is 


Dragon's  Mw+h 


FIG.  247. — Sketch  map  of  Trinidad  showing  petroliferous  areas.  (Based  on 
on  map  by  Wall  and  Sawkins.  Petroliferous  areas  from  map  by  Redwood.) 

possible  to  walk  for  miles  in  the  forests  without  ever  being  out  of 
sight  of  asphalt,  and  in  certain  localities  near  Oropuche  and  on 
Mont  L'Enfer  more  asphalt  than  soil  is  to  be  seen. 

Fig.  247  is  a  map  of  Trinidad  showing  the  position  of  the  meta- 
morphic  belt  in  the  northern  area  as  outlined  by  Wall  and  Sawkins. 
Oil  is  present  in  the  Tertiary  formations,  which  are  sediments 

CUNNINGHAM-CRAIG,  E.  H.:  Oil  Finding,  pp.  6,  44,  74,  75,  102,  London, 
1914. 

RICHARDSON,  CLIFFORD:  The  Modern  Asphalt  Pavement,  New  York,  1905. 

CROSBY,  W.  O.:  Native  Bitumens  and  the  Pitch  Lake  of  Trinidad. '  Am. 
Naturalist,  vol.  13,  p.  240,  1879. 

2CUNNINGHAM-CRAIG,  E.  H.  I  Op.  dt.,  p.   102. 


576  GEOLOGY  OF  PETROLEUM 

formed  under  fluviatile,  deltaic,  and  estuarian  conditions.  Accord- 
ing to  Cunningham-Craig  the  Tertiary  rocks  include  littoral  sand- 
stones and  marine  silts,  thin  calcareous  bands  and  ironstones, 
lignite  seams,  and  oyster  beds,  showing  rapidly  alternating  marine 
and  terrestrial  conditions. 

The  oil  is  in  the  sands  that  lie  between  the  clays  and  is  concen- 
trated in  anticlines.  The  wells  are  from  700  to  2,000  feet  deep, 
and  according  to  Thompson1  many  of  them  have  produced  from 
37,000  to  375,000  barrels  within  one  to  three  years.  Oil  fields 
located  near  La  Brea  produce  a  heavy  oil  from  Miocene  sand.  In 
the  Tabaquite  field  near  the  center  of  the  island  a  very  light  oil  of 
pariffin  base  is  produced  from  Cretaceous  sandstone.  The 
structure  is  anticlinal. 

The  Pitch  Lake  of  La  Brea,  a  village  on  a  small  peninsula  south- 
west of  San  Fernando,  is  about  137  acres  in  extent  and  of  great 
depth.  It  has  produced  over  2,000,000  tons  within  40  years:  It 
is  one  of  the  largest  deposits  of  solid  or  semisolid  bitumen  known. 
The  pitch  at  the  surface  has  the  consistency  of  coal,  so  that  teams 
may  be  driven  on  it.  It  is  chopped  with  axes  and  loaded  into 
carts.  About  140,000  tons  was  produced  in  1909.  As  the  pitch 
is  removed  the  lake  tends  to  maintain  a  level  surface  although  the 
level  of  the  lake  is  sinking.  There  was  also  a  constant  flowage  of 
pitch  to  the  sea  in  a  stream  15  to  18  feet  deep.  Pitch  not  only 
forms  the  seashore  for  the  greater  part  of  a  distance  of  4  miles,  but 
in  front  of  the  village  it  appears  from  beneath  the  sea  as  a  solid 
barrier  reef  which  lies  some  100  yards  from  the  shore  and  is  a  source 
of  danger  to  boatmen  when  the  water  is  rough.  According  to 
Crosby2  the  peninsula  of  La  Brea  owes  its  existence  to  the  protec- 
tion afforded  to  the  land  by  the  asphalt,  which  is  more  resistant 
to  waves  than  the  unconsolidated  clays  and  sands  that  form  the 
coast  to  the  east  and  south.  The  village  of  La  Brea  rests  on  the 
pitch,  and  the  inhabitants  complain  that  their  houses  are  thrown 
out  of  level  by  the  rising  or  sinking  of  the  tarry  formation. 
Inflammable  gas  with  sulphureted  hydrogen  and  salty  sulphurous 
water  issue  near  the  center  of  the  lake.3 

The  material  as  mined  consists  of  about  one-third  bitumen,  one- 

^HOMPSON,  A.  B. :  Oil-Field  Development,  p.  40,  1916. 
"CROSBY,  W.  O.:  Native  Bitumen  and  the  Pitch  Lake  of  Trinidad.     Am. 
Naturalist,  vol.  13,  p.  240,  1879. 

3TnoMPSON,  A.  B. :  Oil-Field  Development,  p.  188,  London,  1916. 


CARIBBEAN  ISLANDS 


577 


J0U0 


puts? 
<f-  aroaj 

j.ioydsuj.0 

^  S2SS0UI 
OUtUDOjUOO 

vuios  £11014$ 


sputos 

•MOJffy 


*°P  f 

MOHdk 

MW 


\\pU05AMp 

' 


FIG.  248.  —  Plan  and  sections  of  Trinidad  asphaltic  lake  region. 
and  Sawkins.)  For  sections  4  and  5,  see  Fig.  249. 


Wall 


578 


GEOLOGY  OF  PETROLEUM 


third  sand,  and  one-third  water.  On  heating,  the  bitumen  lique- 
fies, the  sand  sinks  and  is  separated,  and  the  water  is  driven  off  as 
steam.  According  to  Crosby  the  pitch  is  rich  also  in  vegetable 
remains. 

The  geology  of  the  region  containing  Pitch  Lake  is  shown  by 
Figs.  248  and  249.  The  strata  are  thrown  into  gentle  folds.  As 
shown  by  these  sections,  the  lake  is  situated  in  an  open  syncline. 
Cunningham-Craig,1  however,  who  studied  the  region  at  a  later 
date  than  Wall  and  Sawkins,  in  tracing  the  genesis  of  the  lake, 
states  that  it  has  been  formed  by  the  denudation  of  the  soft  clay 
that  caps  a  petroliferous  sand,  in  an  area  where  it  had  been  thrown 
upward  by  folding.  The  removal  of  the  clay  permitted  the  oil  to 
escape  and  form  the  lake. 

PETROLEUM  PRODUCED  IN  TRINIDAD,  1908-1917 


Barrels 

1908 169 

1909 57,143 

1910 '142  ,857 

1911 285,307 

1912..  .   436,805 


Barrels 

1913 503,616 

1914 643  ,533 

1915 "750,000 

1916 928,581 

1917..                               .  1,599,455 


CUNNINGHAM-CRAIG,  E.  H. :  Oil  Finding,  pp.  90-100,  1914. 


CARIBBEAN  ISLANDS 


579 


r 
-I 

S 


fop 


•; puns 
KflMff 

A  up  pay 


spuos 


r 


w  5vu?p 


FIG.  249. — Sections  of  asphaltic  lake  region,  Trinidad.  (After  Wall  and  Saw- 
kins.)  For  position  of  sections,  see  Fig.  248. 


CHAPTER  XXVIII 
SOUTH  AMERICA 


VENEZUELA 

In  Venezuela!  deposits  of  bitunteri  are  founds  at  many  places. 
The  best  known  is  the  Betmudez  asphalt  lake,  so  called  from  tr|e 
name  of  the  State  in  which  it  is  located.  This  lake  is  near  the  coa|t 
of  the  Gulf  of  Paria,  a  short  distance  from  Pedernales,  in  thb 
eastern  part  of  Venezuela  (Fig.  250)  not  far  from  the  Pitch  Lake 
of  Trinidad.  The  deposit  is  about  2,500  feet  long  in  a  northeasterly 
direction  and  from  300  to  600  feet  wid£.  It  has  yielded  large 
amounts,  of  commercial  asphalt,  which  is>  purer  than  Trinidad 

,  asphalt  and  is  said  to  contain  only  2.14  per  cent  of  earthy  and 
vegetable  matter.  The  deposit  is,  however,  not  as  deep  as  that 
of.  Trinidad.  Oil  springs  and  mud  volcanoes  occur  .also  in  this 

r  region. 

Oil  seeps  and  asphalt  are  found  at  many  places  in  the  vicinity  of 
Lake  Maracaibo.  Clapp1  lists  the  gecurrenees  in  this  region  as 
follows:  tj§T? 

:_  '  ^'  .,-: 

1.  In  the  district  of  Mara,  near  the  River  Lilian  asphalt  lake, 
where  oozings  of  petroleum  cover  considerable  areas. 

2.  At  Bella  Vista,  near  the  city  of  Maracaibo.; 

3.  In  the  district  of  Sucre,  on  the  eastern  shore  of  Lake  Mara- 
caibo, where  signs  of  petroleum  have  been  found  associated  with 
asphalt  deposits. 

4.  On  the  Sardinate  River,  -,[  extending  into  Colombia,  where 
petroleum  is  developed  on  a  sm^ll  scale  and  solc|locally. 

5.  In  the  district  of  Colon,  hi  the  State  of  Zuife,,  south  of  Lake 
Maracaibo.     This  is  the  largest  and  most  access||le  field  in  Vene- 
zuela at  present  developed. 

6.  In  the  Perija  field,  50  miles  west  of  Lake  IM^racaibo. 

West  of  Maracaibo  L,ake  the  rock&dip  eastward,  away  from  the 
Perija  Mountains.  Oil  is  believed  to  hav^accumulated  on  local 
subordinate  folds  in  Cretaceous  rocks.  nxv<w 


,  F.  G.  :  Petroleum  Resources  of  South  Ameri(|&!    Am.  Jnst.  Min, 
Eng.  Bull  130,  pp.  1,764-1,765,  1917. 

580 


SOUTH  AMERICA 


COLOMBIA 


581 


Colombia.— Colombia1  may  be  divided  into  seven  provinces, 
which  are  more  or  less  geographic  units.  Each  province,  accord- 
ing to  White,  has  distinctive  petroliferous  evidence,  structural 


A    MAP  OF 

SOUTH    AMERICA 

SHOWING 
THE  LOCATION  OF  THI 

PETROLEUM  REGIONS 


^Asphalt  or  PttroUum,  afu*  uitk  gal 
•  •••Mi 


_ Fixed  Boundary 

fmndury  Vratttltd 

Main  Bailroadt 
.,,0     |      2     8      4     £     A      1      8      » 


e  m  Hundr»d»  of  UlUt 
01    234    S  0  7  8  fl 

:i 


M»p  OvUlM  bj  Court.ij  of  M«tbei«J<orthnip  WorU.  BuftoJo.  N.T. 


FIG.  250.  —  Index  map  of  South  America,  showing  regions  containing  petro- 
leum, asphalt,  gas  and  oil  shale.  (Based  on  map  by  Clapp  and  Herold.} 


,  K.  D.:  Oil  Development  in  Colombia,  South  America      South- 
western Assoc.  Pet.  Geologists  Bull,  vol.  1,  pp.  157-159,  1917. 


582  GEOLOGY  OF  PETROLEUM 

deformation,   and   stratigraphic   section.     The   seven   provinces 
are  as  follows: 

1.  The  Caribbean  region,  extending  from  the  Gulf  of  Darien  to 
the  mouth  of  the  Magdalena  River,  including  the  Sinu  River  valley 
and  the  lower  part  of  the  Magdalena  River  valley. 

2.  The  Santa  Marta  Mountains  and  the  Goajira  Peninsula. 

3.  The  lower  Magdalena  River  valley,  below  the  falls  at  Honda. 

4.  The  upper  Magdalena  River  valley. 

5.  The  Meta  River  valley  and  the  eastern  slope  of  the  Andes  in 
the  Orinoco  River  drainage  basin. 

6.  The  Lake  Maracaibo  drainage  basin. 

7.  The  Pacific  coast  region. 

In  the  northern  or  Caribbean  region  the  evidences  of  petroleum 
are  mud  volcanoes,  some  covering  acres,  gas  springs,  salt-water 
springs,  and  seeps  of  petroleum  ranging  from  heavy  asphaltic  oils 
with  a  gravity  as  low  as  10°  Baume  through  amber  oils  composed 
almost  entirely  of  the  lubricants  to  white  oils  that  are  practically 
pure  kerosene  and  gasoline.  The  seeps  are  in  general  either  in  the 
shattered  zones  of  faults  of  considerable  displacement  or  in  the 
crushed  cores  of  closely  folded  asymmetric  anticlines.  The  surface 
rocks  are  either  Miocene  or  Pliocene  sediments.  The  Miocene  of 
the  coast  has  a  thickness  of  at  least  8,000  feet. 

According  to  Arnold,1  the  rocks  that  carry  the  oil  are  mostly 
coal-bearing  also  and  are  of  early  Tertiary,  probably  Oligocene 
age.  The  great  bulk  of  the  sediments  are  dark-colored  shales, 
with  sandstone  members;  the  oil  occurs  in  the  sandstones. 

The  Caribbean  district  includes  several  promising  fields.  The 
Turbaco  field  lies  12  to  15  miles  south  of  Cartagena.  Its  surface 
evidence  of  oil  consists  largely  of  mud  volcanoes.  A  medium- 
grade  oil  is  produced. 

The  Tubara  field  is  20  miles  east  of  Cartagena.  As  many  as 
100  mud  volcanoes  are  said  to  occur  in  an  area  of  3  acres  in  the 
vicinity  of  the  wells.  A  Canadian  company  has  drilled  three 
wells  ranging  in  depth  from  700  to  3,018  feet,  at  least  one  of  which 
yielded  7  or  8  barrels  daily  of  oil  having  an  asphalt  base  and  a 
gravity  of  22°  to  26°  Baume.  The  oil  is  associated  with  consider- 
able gas. 

ARNOLD,  RALPH:  Conservation  of  the  Oil  and  Gas  Resources  of  the  Ameri- 
cas. Second  Pan  American  Sci.  Cong.  Proc.,  vol.  3,  pp.  225-227,  1917. 


SOUTH  AMERICA  583 

The  lower  part  of  the  valley  of  Magdalena  River,  extending 
from  200  to  500  miles  from  the  coast,  is  bounded  by  the  Eastern 
and  Central  Andean  ranges  and  in  places  is  100  miles  wide.  This 
area  is  now  being  actively  explored.  The  petroleum  in  the  seeps 
ranges  from  liquid  asphaltum  to  amber  oils.  Gas  springs  and 
sulphur-water  springs  occur.  There  are  also  veins  of  gilsonite  and 
grahamite,  and  asphaltum-impregnated  sandstones.  Most  of  the 
oil  seeps  consist  of  thick  black  asphaltic  oil  having  a  gravity  of 
about  12°  to  14°  Baume.  The  larger  number  of  seeps  come  from 
black  carbonaceous  limestones  and  shales  of  Cretaceous  age, 
though  asphaltic  sandstones,  gilsonite  and  grahamite  veins,  and 
oil  seeps  occur  in  younger  beds. 

The  structure  is  of  the  block-fault  mountain  type.  This  major 
structure  has  been  complicated  by  intense  folding,  parallel  to  the 
Andean  ranges  and  less  intense  transverse  or  cross  folding.  The 
lands  that  may  be  studied  where  the  petroleum-bearing  beds  may 
be  reached  by  the  drill  are,  according  to  White,  confined  to  a  nar- 
row belt  at  the  foot  of  the  two  mountain  ranges. 

The  upper  part  of  the  Magdalena  Valley  is  much  narrower  than 
the  lower  part  and  can  be  studied  across  its  entire  width,  though 
the  older  strata  are  masked  in  places  by  a  covering  of  late  Tertiary 
pyroclastic  rocks.  The  evidence  of  petroleum  consists  of  seeps 
of  thick  black  asphaltic  oils  having  a  gravity  of  14°  Baume  and 
amber  oils  of  18°  Baume.  The  seeps  are  in  general  found  along 
the  lines  of  faulting,  where  the  black  carbonaceous  limestones  and 
shales  of  Cretaceous  age  have  been  brought  to  or  very  close  to  the 
surface.  Seeps  occur  also  in  rocks  of  later  age,  especially  the 
Tertiary  tuffs. 

In  the  Lake  Maracaibo  drainage  basin,  in  the  Department  of 
Santander,  numerous  seeps  of  high-grade  oil,  as  stated  by  White, 
are  located  on  the  crest  of  an  asymmetric  anticline. 

The  Magdalena  and  Santander  districts  together  cover  a  belt 
approximately  200  miles  long  and  50  miles  wide,  or  10,000  square 
miles,  where  oil  seeps  are  numerous.  At  Pamplona,  near  the  Vene- 
zuelan frontier,  a  small  refinery  is  operated.  The  oil  in  this  dis- 
trict occurs  in  the  Cretaceous  limestones  and  sandstones  and  in  the 
coal-bearing  lower  Tertiary  (probably  Oligocene)  beds,  where 
sandstones  are  the  reservoirs.  Well-defined  anticlines,  in  places 
overturned,  and  possibly  fault  zones  in  the  Cretaceous  rocks  are 
said  to  afford  favorable  structure  for  accumulation.  According 


584 


GEOLOGY  OF  PETROLEUM 


to  Aughinbaugh,1  foreign  editor  of  the  New  York  Commercial,  a 
field  in  Colombia  near  the  Venezuela  line  has  been  developed 
which  promises  to  become  very  large.  The  Caribbean  Petroleum 
Co.,  he  says,  has  brought  in  17  wells,  some  of  them  gushers.  In 
this  region,  at  a  depth  of  about  1,000  feet,  a  gusher  yielding  12,000 
barrels  a  day  was  brought  in. 

In  the  Tolima  district  are  grouped  the  occurrences  in  the  upper 
Magdalena  basin,  in  the  departments  of  Cundinamarca  and  Tolima, 
and  on  the  edge  of  the  San  Martin  and  Casanare  plains.  The  oil- 
bearing  rocks  are  probably  of  Cretaceous  or  Tertiary  age  and  form 
a  continuation  of  those  in  the  Santander  belt,  to  the  north. 

The  Pacific  district  includes  a  belt  60  or  70  miles  long  extending 
up  the  Pacific  coast  north  of  Buenaventura  to  Baudo  River  and 
reaching  inland  to  Atrato  River  at  Quibdo  and  as  far  south  as 
Cali,  on  the  Cauca  River.  On  Baudo  River  oil  is  associated  with 
the  "coal  series"  and  probably  occurs  in  a  southwestward  extension 
of  the  Caribbean  coastal  belt. 

AREAS  INCLUDED  IN  THE   PROSPECTIVE  OIL  DISTRICTS  OF  COLOMBIA,   IN 

SQUARE  MILES'* 


District 

Area 

Possible 
Oil 
Territory 

Proved 
Oil 
Territory 

Caribbean  

15  000 

300 

1 

Pacific  

1  800 

18 

Magdalena-Santander  

10  000 

200 

1 

Tolima  

7  500 

100 

34  ,300 

618 

2 

°ARNOLD,  RALPH:  Conservation  of  Oil  and  Gas  Resources  of  the  Americas.  Second  Pan 
American  Sci.  Cong.  Proc.,  vol.  3,  p.  225,  1917. 

PERU 

Peru2  is  one  of  the  leading  oil-producing  countries  in  South 
America.  Oil  is  found  in  the  northwestern  part  of  the  Republic 
(Fig.  251),  on  the  coast  near  the  Ecuador  boundary,  and  in  the 
Lake  Titicaca  region.  The  coastal  belt  extends  southward  along 

'AUGHINBAUGH,  W.  E. :  Supplement  to  New  York  Commercial,  not  dated. 

*MARSTERS,  V.  F. :  Informs  Preliniinar  sobre  la  zona  Petrolifera  del  norte 
del  Peru.  Cuerp.  ing.  Minas  del  Peru  Bol  50,  pp.  1-150,  1907. 


SOUTH  AMERICA  585 

the  Pacific  Ocean  from  the  Ecuador  frontier  for  180  miles,  to  and 
beyond  Paita,  and  is  bounded  on  the  east  by  spurs  of  the  Andes. 
It  is  about  30  miles  wide  and  occupies  the  region  near  Tumbez 
and  the  northern  part  of  the  province  of  Piura.  Asphaltites  and 
asphaltic  clays  are  common  in  Peru.  The  petroliferous  rocks  are 
porous  sandstones  of  Eocene  age.  Fossils  in  the  petroliferous 
series  closely  resemble  those  of  the  California  Eocene.  The 
sequence  of  formations  from  east  to  west,  as  described  by  Deustua,1 
is  as  follows. 

Commencing  in  the  mountain  region  of  La  Brea,  there  are: 
(1)  A  series  of  crystalline  rocks!  dioritic  in  the  main,  which  may  be 
regarded  as  the  basal  formation  of  the  chain;  (2)  a  mass  of  sedi- 
ments composed  almost  entirely  of  shales  metamorphosed  into 
slate$,  and  greatly  folded  and  faulted ;  these  constitute  the  western 
flanks  of  La  Brea;  (3)  a  series  of  thick  beds  of  sandstones,  which 
are  highly  indurated  and  unconformable  to  (2)  and  whicl|  also 
form1  a  part  of  the  flanks  of  La  Brea;  (4)  a  series  of  alternating  beds 
of  sandstones  and  clays  or  shales,  unconformable  to  (3)  and  extend- 
ing from  the  base  of  La  Brea  Mountain  to  the  sea-shore ;  the  lower 
beds  of  this  series  inclose  the  oil-bearing  strata;  (5)  a  series  of 
horizontal  deposits,  unconformable  to  (4),  forming  the  plateau  of 
the  "tablazo"  and  composed  of  clays  of  different  colors;  alt^rnat- 
ing  with  a  few  beds  of  loose  and  little-hardened  sandstones;  both 
rocks  are  capped  by  thick  beds  of  conglomerates.  There  are 
several  conglomerates  in  division  4,  at  least  some  of  which  jmark 
unconformities.  The  angular  difference,  however,  betweeji  the 
beds!  above  and  below  ^he  unconformities  is  slight  as  compared 
with;  the  regional  dips. 

Tie  metamorphism  of  the  shales  (division  2)  is  due  to  the  Intru- 
sive rock  (1 ) ,  and  these  rocks  form  the  principal  base  of  the  northern 
oil-bearing  region,  and  the  eastern  limit  of  the  oldest  sedinkents. 
The  rocks  of  division  3  are  later  than  the  metamorphosed  shales, 
but  older  than  those  of  division  4,  which  form  a  series  of  anticlinal 
and  synclinal  flexures,  terminating  in  a  wide  anticline  along  the 
coast  line.  The  upper  sandstones  are  gray  and  coarse  grained, 
and  are  intercalated  with  red  and  yellow  clays  rich  in  fossils;  the 
lower  oil-bearing  sandstones  are  dark  and  coarse  grained,  and  are 

'DuESTUA,  R.  A.:  La  Industria  del  Petr61eo  en  el  Peril  durante  1915,  2d  ed., 
Lima,  1916,  quoted  from  CLAPP,  F.  G.,  Am.  Inst.  Min.  Eng.  Bull.  130,  p.  1,751, 
1917.  .The  original  is  not  accessible  to  me. — W.  H.  E. 


586 


GEOLOGY  OF  PETROLEUM 


intercalated  with  thick  clayey  beds  which  are  greenish,  nonfossili- 
ferous,  and  more  compact  than  the  upper  argillaceous  beds. 

The  plateau  deposits  show  three  well-marked  fossiliferous  beds. 
The  conglomeratic  cap  is  formed  of  pebbles,  breccia  remains,  and 
coral  reefs,  strongly  cemented.  Fossils  are  found  on  the  surface, 
the  species  of  which  are  identical  with  those  now  living  in  the  sea, 


Sc&le 

OSlOlSZOZS 


so  Km 


FIG.  251. — Sketch  map  showing  location  of  oil  fields  in  northern  Peru.  (Based 
on  map  by  Marsters.) 

near  the  shore.     It  is  obvious  that  the  beds  were  laid  down  in 
shallow  water. 

The  regional  dip  of  the  country  is  westward,  away  from  the 
mountains,  but  in  the  oil  fields  the  beds  dip  east  (Fig.  252).  The 
principal  fields  are  associated  with  anticlines.  No  large  gushers 


SOUTH  AMERICA 


587 


the  wells  yield  over  100 
not  very  long-lived,  and 


I 


II 


have  yet  been  brought  in,  but  some  of 
barrels  a  day.   The  initial  production  is 
after  a  few  weeks  or  months 
it  settles  down  to  4  to  10  bar-     * 
rels  a  day,  which  appears  to  be      \ 
maintained  for  several  years. 
The  depth  of  the  wells  ranges 
from  700  to  3,000  feet,   the 
average  being  probably  about 
1,500  feet. 

The  Zorritos  field  (Fig.  253) 
is  the  northernmost  of  the 
Peruvian  fields  and  lies  a  few 
miles  south  of  Tumbez,  on  a 
narrow,  sharp  fold  that  runs 
parallel  with  the  coast.  The 
producing  territory  extends 
along  the  coast  for  about  4 
miles,  most  of  the  producing 
wells  being  drilled  at  the 
water's  edge.  The  oil  is  of  as- 
phalt base  and  ranges  from 
about  37°  to  43°  Baume.  The 
wells  are  from  600  to  850  feet 
deep  and  yield  an  average  of  6 
barrels  a  day.  The  fold  is 
faulted  longitudinally.  The 
highest  part  of  it  is  dry.  .This 
may  be  due  to  low  water  head 
in  the  sands,  so  that  the  oil  has 
not  been  forced  to  the  crest  of 
the  anticline,  or  it  may  be  due 
to  an  overthrust  fault  on  the 
south  end. 

There  are  at  Zorritos  three 
principal  sands,  one  at  a  depth 
of  800  feet,  one  at  1,200  feet, 
and  one  at  1,700  feet.  The  up- 
per two  sands  have  been 
practically  exhausted,  and  the  present  output  is  obtained  from 


I 
il 


i 

II 


I 


.2 


588  GEOLOGY  OF  PETROLEUM 

the  deep  one.  The  sands  are  thick,  soft,  and  shaly.  The  production 
averages  about  8  barrels  a  day  per  well.  No  big  wells  have  been 
drilled.  Owing  to  the  very  soft  and  shaly  nature  of  the  sands 
shooting  is  out  of  the  question. 

Producing  wells  recently  sunk  at  Punta  Restin  and  Cabo  Blanco 
are  on  a  narrow  compressed  and  longitudinally  faulted  anticline 
running  close  to  the  beach.  Much  of  the  west  flank  of  the  anti- 
cline is  in  the  sea  and  has  not  been  drilled,  owing,  it  is  said,  to 
refusal  of  the  Government  to  permit  drillingjn  the  sea, 

La  Brea  is  a  seep  lying  inland  close  to  the  base  of  the  Amotape 
Mountains.  The  oil  is  derived  from  the  basal  conglomerate  and 
coarse  sandstone  series.  It  has  accumulated  in  a  small  dome  on  a 
very  extensive  anticline,  which  is  at  this  point  capped  by  several 
hundred  feet  of  soft  shale.  Nearly  everywhere  else  this  anticline 
is  deeply  eroded,  exposing  the  sands.  The  dome  is  faulted  and 
the  seep  is  due  to  leakage  along  fault  planes. 


w 


FIG.  253. — Generalized   ideal  geological  section  showing  structure  Mancora 
Valley,  between  Zorritos  and  Lobitos,  Peru  (looking  south.) 

The  Lobitos  field  lies  about  110  kilometers  south  of  Zorritos,  and 
comprises  a  proved  area  of  25  square  miles.  In  character  of  the 
oil  and  productivity  of  the  wells  this  field  is  similar  to  Zorritos. 

The  Negritos  field  is  the  southernmost  one  developed  of  the 
coastal  areas.  It  is  40  miles  north  of  Paita  and  includes  about  150 
square  miles  of  proved  territory  comprised  in  the  hacienda  La 
Mina  Brea  and  Parinas.  The  oil  is  brown  and  ranges  in  gravity 
from  35°  to  38°  Baume.  The  wells  range  in  depth  from  500  to 
3,000  feet  and  in  individual  production  from  over  800  barrels  daily 
to  an  average  settled  production  of  4  to  7  barrels.  An  asphalt 
seep,  La  Brea,  is  found  11  miles  east  of  the  field.  The  rocks  in  the 
Negritos  field  dip  in  general  away  from  the  mountains.  Locally 


SOUTH  AMERICA  589 

there  are  reversals  of  dip,  and  the  field  is  probably  on  the  eastern 
flank  of  a  great  anticline  (Fig.  254).  The  dip  of  the  sandstone 
and  clay  at  the  south  end  of  the  region  is  southeast;  farther  north- 
ward the  dip  becomes  east;  and  north  of  Negritos  it  is  northeast. 
Possibly  the  field  is  a  dome  with  the  west  side  below  the  sea.  The 
eastern  flanks  of  the  fold  present  a  number  of  secondary  folds  and 
local  faults,  which  alter  somewhat  the  distribution  of  the  oil  zones. 
The  bore  holes  made  along  the  flanks  have  yielded  the  best  results. 
.Along  the  anticlinal  axis  or  ridge  itself  the  results  have  been  poor, 
and  far  to  the  east  of  the  flanks  there  is  danger  of  encountering  the 
corresponding  syncline,  where  the  probability  of  obtaining  oil  is 
remote. 

From  a  depth  of  45  to  1,000  feet  as  many  as  seven  oil-bearing 
formations  have  been  encountered,  but  as  a  rule  these  are  of  little 
.  value,  the  most  productive  beds  being  those  found  below  depths 
of  1,500  feet. 

The  eastward  dip  is  the  reverse  of  the  regional  dip  of  the 
country.  The  most  reasonable  supposition  is  that  the  normal 
regional  westward  dip  is  resumed  west  of  the  Negritos  and  Lobitos 
fields,  beneath  the  sea  floor.  The  monocline  is  then  merely  the 
eastern  (reverse  dip)  side  of  a  huge  anticline.  However,  some  of 
the  oil  is  produced  from  relatively  shallow  wells  out  on  the  flank 
of  the  fold.  As  the  dip  at  Negritos  and  Lobitos  averages  about 
20°^  it  follows  that  some  of  the  producing  beds  crop  out  on  the 
surface  within  the  limits  of  the  field  and  that  the  oil  must  be 
accumulated  in  lenticular  sands  (Fig.  254).  The  oil  at  Negritos 
has  probably  accumulated  both  in  anticlines  and  in  sealed  beds. 

The  Titicaca  field  lies  high  in  the  Andes,  8  miles  from  Lake 
Titicaca,  near  the  Bolivian  frontier.  Exudations  of  oil  are  numer- 
ous, and  according  to  Duestua1  oil  issues  in  boiling  springs.  The 
rocks  are  limestones,  clays,  and  sandstones.  An  anticline  is  said 
to  extend  N.  40°  W.  through  the  field,  and  the  formations  on  its 
flanks  are  much  disturbed  by  faulting  and  folding. 

Ten  wells  had  been  drilled  up  to  1908,  with  varying  results. 
Although  the  initial  production  in  some  wells  has  been  as  high  as 
900  barrels  daily,  the  output  falls  rapidly.  The  oil  is  unlike  that 
of  the  northern  fields  of  Peru,  as  it  contains  about  5  per  cent  of 
paraffin  wax  and  40  to  50  per  cent  of  kerosene. 

JDuESTUA,  R.  A.:  La  Industria  cjel  Petr61eo  eq  el  Perfl  dqrante  1915, 
Lima,  1916. 


590  GEOLOGY  OF  PETROLEUM 

PETROLEUM  PRODUCED  IN  PERU,   1907-1917,  IN  BARRELS  OF  42  GALLONS 


Year 

Lobitos 

Negritos 

Zorritos 

Lake 
Titicaca 
(Huan- 
cane) 

Lagu- 
nitos 

Total 

Barrels 

Metric 
Tons0 

1907 

6279  ,000 
319  ,898 
429,195 
400  ,080 
391  ,290 
587  ,048 
557  ,355 
504  ,743 
664  ,972 
654  ,060 
686  ,595 

396  ,750 
543  ,750 
740  ,070 
773  ,025 
882  ,698 
1  ,071  ,000 
1  ,136  ,490 
1  ,032  ,210 
1  ,355  ,925 
cl  ,822  ,733 
cl  ,771  ,560 

65  ,476 
71  ,429 
70  ,750 
107  ,000 
64  ,286 
78  ,095 
83  ,343 
88,136 
72  ,736 
73  ,852 
75  ,262 

15  ,000 
&76  ,103 
676,103 
650  ,000 
630  ,000 
615  ,000 
6  10  ,000 
610  ,000 
61  ,000 

756  ,226 
,011  ,180 
,316,118 
,3301105 
,368  ,274 
,751  ,143 

100  ,830 
134  ,824 
175  ,482 
177  ,347 
182  ,436 
233  ,486 
284  ,434 
255  ,707 
331  ,633 
340  ,086 
337  ,789 

1908 

1909 

1910 

1911 

1912 

1913  

346  ,073 
282  ,713 
392  ,618 
(d) 
(*> 

2,133,261 
1  ,917  ,802 
2  ,487  ,251 
2  ,550  ,645 
2,533,417 

1914  

1915  

1916  

1917  

"One  metric  ton=7.5  barrels. 
6Estimated. 


clncludes  Lagunitos. 
^Included  in  Negritos. 


£. 


FIG.  254. — Generalized  geological  section,  showing  structure  of  Negritos  oil 
field,  Peru  (looking  south.)  The  western  part  of  section  is  hypothetical. 

ECUADOR 

The  eastern  range  of  the  Andes  in  Ecuador1  consists  of  rocks  of 
Archean  age;  the  coastal  regions  consist  of  Tertiary  deposits;  and 
the  intermediate  region,  which  includes  the  western  range  of  the 
Andes  and  the  inter- Andean  region,  is  made  up  mainly  of  Cre- 
taceous sedimentary  and  eruptive  rocks.  Only  the  western  two 
of  these  three  belts  has  oil  possibilities. 

In  the  Santa  Elena  field, 2  64  miles  west  of  Guayaquil,  oil  seeps 

WOLF,  W.  A. :  Sketch  of  the  Geology  of  Ecuador.  Min.  and  Sci.  Press, 
vol.  105,  pp.  110-111,  1912. 

ARNOLD,  RALPH  :  Conservation  of  the  Oil  and  Gas  Resources  of  the  Ameri- 
cas. Econ.  Geology,  vol.  11,  p.  309,  1916. 


SOUTH  AMERICA  591 

and  desiccated  petroleum  residues  have  long  been  known.  This 
district  is  a  continuation  of  the  Peruvian  coast  fields.  The  oil  is 
derived  from  sandstones  and  shales  of  Eocene  age.  Forty  dug 
wells  at  Santa  Paula  yield  small  quantities  of  heavy  oil,  which  is 
taken  to  the  coast  on  donkeys.  A  number  of  dug  wells  were 
formerly  operated  at  Achagian.  The  oil  ranges  in  gravity  between 
12°  and  22°  Baume.  Oil  springs  are  reported  on  the  east  side  of 
the  Andes,  130  miles  north  of  east  of  Guayaquil,  and  at  points  in 
the  coastal  plain  north  of  Guayaquil,  particularly  at  Atacames. 

The  topography  of  the  Santa  Elena  field  is  hilly,  with  many 
valleys  and  ravines,  portions  of  which  grade  into  a  plain  bordering 
the  Pacific  Ocean  and  Bay  of  Santa  Elena.  The  climate  of  the 
Santa  Elena  fields  is  described  as  healthy.  The  whole  of  the 
peninsula  between  the  Pacific  Ocean  and  the  Bay  of  Santa  Elena 
is  considered  as  more  or  less  petroliferous.  Stephan1  states  that 
the  large  supply  of  oil  at  present  obtained  at  Aguiquimi  and  at 
Santa  Elena  Paula  clearly  points  out  the  existence  of  a  rich  oil 
zone  at  a  deeper  horizon  at  these  points.  Petroleum  is  found  at 
many  places  near  the  promontory  of  Santa  Elena.  According  to 
unpublished  reports  by  Charles  Haddock,  seeps  of  oil  are  found  in 
many  places  over  an  area  of  600  square  miles.  To  judge  from  the 
depths  at  which  it  is  found  in  the  adjacent  field  of  Peru  it  is 
believed  that  oil  will  be  reached  here  at  about  1,000  feet. 

ARGENTINA  AND  BOLIVIA 

There  are  three  oil-bearing  districts  in  Argentina2 — the  Como- 
doro  Rivadavia  district,  on  the  Atlantic  coast  of  Patagonia,  and 
the  Salta-Jujuy  and  Mendoza-Neuquen  districts,  in  the  Andean 
region. 

In  the  Rivadavia  district  oil  was  discovered  in  1907,  when  a 
boring  was  being  sunk  for  water.  The  oil-yielding  formation  is  a 
Cretaceous  coarse,  pebbly  sandstone,  which  lies  on  schist  and 
granite  and  is  unconformably  overlain  by  Eocene  and  later  Ter- 
tiary tuffaceous  and  fossiliferous  beds.  The  origin  of  the  oil  is 
obscure.  The  beds  dip  southeast  at  a  low  angle,  not  exceeding  12 

STEPHAN,  M.  J.:  Unpublished  Report,  quoted  by  CLAPP,  F.  G.,  Petroleum 
Resources  of  South  America.  Am.  Inst.  Min.  Eng.  Bull.  130,  pp.  1,776- 
1,777,  1917. 

'ARNOLD,  RALPH  :  Conservation  of  the  Oil  and  Gas  Resources  of  the  Amer- 
icas. Second  Pan  American  Sci.  Cong.  Proc.,  vol.  3,  pp.  207-237,  1917; 
Econ.  Geology,  vol.  11,  pp.  203-222,  299-326,  1917. 


592 


GEOLOGY  OF  PETROLEUM 


feet  to  the  mile,  and  are  said  to  occupy  a  broad  syneline  with 
minor  warpings.  The  oil  occurs  in  flat  domes  at  a  depth  of  1,800 
to  1,900  feet,  and  Herold1  states  that  the  structural  conditions 
are  shown  on  the  surface  and  that  conditions  favor  an  extension 
of  the  producing  area.  The  oil  is  of  asphaltic  base  and  ranges  in 
gravity  from  18°  to  24°  Baume.  The  wells  are  rather  small  pro- 
ducers, so  far  averaging  less  than  100  barrels  daily.  The  oil  pro- 
duced in  Argentina  comes  entirely  from  the  Comodoro  Rivadavia 
field  and  is  consumed  in  the  country,  principally  for  fuel. 

PETROLEUM  PRODUCED  IN  ARGENTINA,  1908-1917 


a 

United 

United 

Year 

Metric 

States 

Year 

Metric 

States 

• 

Tons 

Barrels 

Tons 

Barrels 

J      ..  • 

'      -' 
1908  

1  ,680 

11  ,472 

1913  

19  ,050 

130,618 

1909 

2  700 

18  ,431 

1914.  

40  ,530 

275  ,500 

1910   ... 

3,050 

20,753 

1&15  

75  ,900 

516  ,120 

1911 

1  ,920 

13  ,119 

1916  

116  ,000 

796  ,920 

1912.  .  .  ;  

6,850 

47  ,007 

1917  

166  ,871 

1  ,144  ,737 

The  oil  field  of  northern  Argentina  and  Bolivia2  extends  in  a 
narrow  belt  from  the  north-central  part  of  the  Province  of  Salta, 
Argentina,  northward  into  the  central  part  of  Bolivia.  This  belt 
passes  through  the  border  town  of  Yacuiva  and  extends  from  18° 
to  23°  south  latitude. 

The  oil  region  lies  between  a  mountainous  country  to  the  west 
and  extensive  plains  to  the  east.  A  series  of  mountain  ranges,  with 
parallel  northerly  trend,  stretch  westward  with  increasing  altitude 
toward  the  great  Andes  Range.  Between  these  ranges  are  long, 
narrow  valleys  at  altitudes  of  10,000  to  12,500  feet  above  the  sea. 

The  mountainous  relief  has  been  produced  by  the  same  dynamic 
forces  which  caused  the  uplifting  of  the  main  Andes  Range.  The 
easternmost  range,  known  as  the  Sierra.de  Aguaragiie,  with  its 

HEROLD,  S.  C. :  Petroleum  in  the  Argentine  Republic.  Mining  and  Metal' 
lurgy,  sec.  12,  No.  158,  pp.  1-5,  1920. 

»HEROLD;  STANLEY  C. :  The  Economic  and  Geologic  Conditions  Pertaining 
to  the  Occurrence  of  Oil  in  the  North  Argentine-Bolivian  Field  of  South 
America.  Amer.  Inst.  Min.  Eng.  Bull,  pp.  1,503-1,522,  1918. 


SOUTH  AMERICA  593 

northern  extension  in  the  Sierras  de  Santa  Cruz,  constitutes  the 
frontal  range,  extending  from  north  to  south  approximately  300 
miles,  with  altitudes  between  1,000  and  3,000  feet  above  the  level 
of  the  adjoining  plains. 

Seeps  of  oil  and  asphalt  deposits  have  been  known  to  exist  in 
this  part  of  the  continent  for  many  years.  Several  springs  are 
very  persistent  in  their  flow,  though  each  produces  only  2  or  3 
quarts  a  day.  Among  the  best  known,  according  to  Herold,  are 
the  following,  named  in  geographic  order  from  south  to  north : 

Creek  Department 

Galarza Oran  (Argentina) 

Iquira Oran  (Argentina) 

Agua  Salada  (Ipaquazu) Tarija  (Bolivia) 

Los  Monos  (Villamontes) Tarija  (Bolivia) 

Caigua  (Villamontes) Tarija  (Bolivia) 

Peima Tarija  (Bolivia) 

Oquita Sucre  (Bolivia) 

Mandiyuti Sucre  (Bolivia) 

Espejos  (Santa  Cruz) Santa  Cruz  (Bolivia) 

Most  of  the  oils  are  of  paraffin  base,  though  some  of  the  heavy 
oils  contain  some  asphalt.  Usually  a  small  amount  of  sulphur  is 
present. 


INDEX 


Absorption  method  of  oil  recovery,  77 
Accumulation  of  petroleum,  105 
Acid  water,  40 
Aclines,  oil  in,  153 
Adhesion,  oil  retained  by,  189 
Aerated  sands,  48 
Age  of  petroleum-bearing  strata,  12 
Ahwaz  anticline,  Persia,  548 
Alabama,  gas  possibilities,  241 

map  of,  361 

oil  possibilities,  247,  360 
Alaska,  oil  fields  of,  470 
Albertite,  17 
Albertite  dike,  New  Brunswick,  29, 

482 
Albert,    New   Brunswick,    oil   seeps, 

23 
Albert  oil  shale,  New  Brunswick,  29, 

38,  483 

Alberta,  Canada,  oil  and  gas  fields  of, 
485 

tar  sands  of,  491 
Algeria,  oil  possibilities  of,  11 
Aliat,  Russia,  oil  lake,  25 
Allen  oil  field,  Texas,  334 
Allendale  oil  field,  Illinois,  264 
Alsace,  oil  fields  of,  509 

coal  seams  in  petroliferous  strata 
of,  88 

geothermal  gradient,  94 

structure  of,  130 
Ambrite,  17 
American  rig,  6 
Amount  of  oil  in  rocks,  109 
Amplitude  of  folds,  131 
Anaerobic  bacteria,  40,  80 
Analyses  of  petroleum,  74 
Angelina  flexure,  Texas  and  Louisi- 
ana, 348 
Animal  remains  in  oil  formations,  83 


Anse  la  Butte  field,  Louisiana,  371 
Anticlinal  ring  and  funnel  structure, 

136 
Anticlines 

amplitudes  of,  131 

oil  in,  105,  120,  123 

origin  of,  134 

shapes  of,  133 
Anticlinal  theory,  105 
Appalachian  geosyncline,  143 

Clinton  gas  field  of,  142 
Appalachian  oil  field,  206 

area  of  pools  in,  208 

carbon  ratios  in  coals  of,  173 

sections  of,  154,  210,  211,  213, 
214,  216 

structure  of,  120,  208,  216 

surface  indications  in,  207 

temperatures    at   time    of   deep 

burial,  93 

Appalachian  plateau,  198 
Arakan  Islands,  mud  volcanoes  of,  37 
Arbuckle  Mountains,  199,  275 
Argentine  oil  fields,  591 

estimated  production,  5 
Arid  conditions  and  oil  formation,  90 
Arkansas  gas  fields  (Fort  Smith),  306 

reservoir  rocks  of,  50 

Stephensville  gas  wells,  356 
Arrangements  of  folds,  137 
Arrangements  of  oil  and  water,  105 
Arroyo  Grande  oil  field,  California, 

462 
Asphalt,  definition,  1 

on  faults,  171,  172 

origin  of,  26 

uses  of,  3 
Asphaltic  oils,  73 
Asphaltic  seals  of  reservoirs,  141 
Asymmetry  of  folds,  133 
Augusta  Kansas,  field,  313 
Australia  gas  field.  569 


594 


INDEX 


595 


B 


Bacteria,  work  of  in  oil  formation, 

40,  84 
Bagdad,  Asia  Minor,  oil  field  near, 

546 

Baicoi,  Rumania,  oil  field,  136,  529 
Baku,  Russia,  oil  fields  of,  535 

mud  volcanoes,  21,  37 

reservoir  rocks,  55 

salt  water  in,  50 

structures  of,  130 
Balakany,  Russia,  oil  field,  540 

section  of,  130 
Balcones  fault,  Texas,  338 
Balik  Papan,  Borneo,  oil  field,  560 
Balls,  pore  space  between,  43 
Barbadoes  Island,  oil  field  of,  573,  574 

burnt  shale  of,  39 

Manjak  in,  20 
Bartlesville  oil  sand 

photograph  of,  61 

porosity  of,  62 

production  of,  54 

Bartlesville,  Oklahoma,  oil  field,  297 
Basins,  oil  in,  124 
Basinward  folds,  oil  accumulation  in, 

137 

Bates  Hole  anticline,  Wyoming,  392 
Batson  pool,  Texas,  370 
Baudo  River,  oil  seeps  on,  23 
Baume*  scale,  69 

conversion  to,  70 
Beaumont,  Texas,  oil  near,  365 
Becieu,  Rumania,  oil  field,  532 
Bedding  planes, 

porosity  of,  44 

oil  seeps,  50 

Beggs,  Oklahoma,  field,  303 
Behavior  of  oil  wells,  183 
Belton  oil  field,  Missouri,  314 
Bend  Arch,  Texas,  map  of,  332 

sections  of,  331,  333 
Benzene  series,  72 
Berca,  Rumania,  oil  fields,  532 

oil  seeps,  50 
Berea  oil  sand,  in  Ohio,  228 

in  Woodfield  quadrangle,  228 


Berea  sand  oil  field,  143,  145 
Bermudez  asphalt  lake,   Venezuela, 

26,  580 
Bibi  Eibat  oil  field,  Baku,  Russia,  540 

geothermal  gradient  at,  94 

mud  volcanoes  of,  21,  37 

oil  sand  of,  38 

Bighorn  basin,  Wyoming,  oil  fields 
of,  397 

salt  water  in,  50 

Big  Muddy  dome,  Wyoming,  385 
Billings,  Montana,  geology  near,  411 

Billings,  Oklahoma,  298 
Binagadi,  Russia,  oil  field,  146,  540 
Biochemical  processes  in  oil  forma- 
tion, 84 

Birch  Creek-Sun  River  area,  Mon- 
tana, 421 

Bird  Creek  pool,  Oklahoma,  297 
Bitumen,    in    quicksilver    veins    of 
California,  20 

in  vanadium  veins  of  Peru,  26 

origin  of,  1 

uses  of,  3 

Bituminous  dikes,  29 
Bituminous  hydrocarbons,  17 
Bituminous  rocks,  27 
Blackfeet     Indian     reservation,     oil 

possibilities  in,  421,  426 
Blossom  sand,  350 

salt  water  in,  49 

Bog  Boga,  Baku,  Russia,  21,  365,  540 
Bolivia,  oil  fields  of,  591 
Bonanza  dome,  Wyoming,  407 
Bone    deposits    in    oil    springs    and 

asphalt,  27 
Borneo,  oil  fields  of,  560 

coast  eruptions  of  oil,  25 
Boryslaw,  Galicia,  oil  fields  of,  520 

salt  waters  of,  50 

structure  in,  130 
Boulder,  Colorado,  oil  field,  431 
Bow  Island,  Canada,  gas  field  of,  491 
Bowdoin  dome,  Montana,  426 
Brazoria  County,  Texas,  oil  in,  370 
Brea,  17 

Bremen,  Ohio,  pool,  48 
Brenning  basin,  Wyoming,  149 


596 


INDEX 


Brine  in  oil  fields,  40,  48 

Bristow  quadrangle,  Oklahoma,  295 

Brownwood,  Texas,  67 

Buck  Creek,  Wyoming,  oil  field,  394 

Buffalo  basin  anticline,  Wyoming,  407 

Building  stones,  porosity  of,  62 

Bull  Bayou,  Louisiana,  oil  field,  131, 

350 

Burkburnett,  Texas,  oil  field,  324,  326 
Burke  pool,  Texas,  341 
Burl's  Creek,  Alaska,  oil  occurrences 

near,  471 
Burma  oil  fields,  130,  133,  553 

mud  dikes  of,  38 
Burnt  Hill,  Barbadoes,  39 
Burnt  shale,  39 
Busra,  Asia  Minor,  oil  occurrences 

in,  546 

Busseyville,  Kentucky,  oil  field,  244 
Bustenari,  Rumania,  oil  field,  530 
Butane,  72 
Byron  dome,  Wyoming,  405 


Cable  drilled  wells,  101 

Caddo,  Louisiana,  oil  field,  350,  351 

gas  of,  35 

"pimples"  of,  37 

salt  water  of,  49 
Caddo,  Texas,  oil  field,  334 
Calgary,  Canada,  oil  field,  475,  485 

oil  of,  68 
California,  oil  fields  of,  442,  443 

bitumens  of,  27 

salt  waters  of,  51 

structures  of,  128 
California  quicksilver  veins,  bitumen 

in,  26 

Campini,  Rumania,  oil  field,  529 
Canada,  oil  fields  of,  475 

estimated  probable  future  of,  11 

production  of,  4 
Canadian  rig,  6 
Caney,  Kansas,  section  of,  312 
Canyon  City  embayment,  Colorado, 

430 
Capillary  openings,  41 


Capillary  theory,  108,  109 

Carbon  ratios  of  coals,  relation  to  oil 

fields,  173,  212 
Carbon  tetrachloride,  28 
Carbonates,  deposition  of  in  well  cas- 
ings, 186 

Caribbean  Islands,  571 
Carlinville,  Illinois,  oil  field,  264 
Cartagena,  Columbia,  oil  field,  582 
Casinghead  gas,  77 
Casings,  salting  of,  52,  186 
Caspian  Sea  oil  fields,  533 

gas  seeps,  6,  533 

Cat  Creek  anticline,  Montana,  410 
Catskill  formation,  oil  in,  108 
Catskill  sands,  degree  of  saturation 

of,  154 
origin  of,  154 

Caucasus,  oil  resources  of,  11 
Cement,  Oklahoma,  323 
Central  Wyoming,  oil  structures  of, 

290 

Cereous  hydrocarbons,  17 
Chapopoti,  17 

Chart  for  determining  dips,  100 
Chatfield,  Texas,  field,  339 
Chaves  County,  New  Mexico,  field, 

439 
Cheleken  Island,   Russia,  oil  fields, 

544 

mud  volcanoes,  37 
salt  springs,  22 
structures  of,  130 
Chiarsukh,  Mesopotamia,  oil  springs, 

546 

Chieti,  Italy,  oil  field,  515 
China,  oil  field  of,  568 
Chloroform  test  for  oil,  28 
Chlorophyl  in  diatoms,  86 
Choctaw  fault,  Oklahoma,  relation  to 

oil  pools,  174 
Cincinnati  arch,  198,  248 

axis  of,  in  Kentucky,  235 
axis  of,  in  Ontario,  477 
Circles  of  anticlinal  oil  pools,  137 
City  oil  field,  Los  Angeles,  California, 

464 
Clark  County,  Illinois,  oil  fields,  262 


INDEX 


597 


Classification  of  oil  reservoirs,  123 
Clay,  effect  on  porosity  of  sands,  58, 
63 

particles,  sinking  of  oil  by,  84 

porosity  of,  41 
Clay  County,  Texas,  324 
Cleveland,  Ohio,  gas  wells  of,  157 

mud  dikes  of,  38 
Clinton  sand  gas  field,  Ohio,  142,  229, 

231,  481 
Closed  fold,  96 
Closure,  99 
Coal  beds,  relation  to  petroliferous 

strata,  88 

Coal,  bitumen  in,  26 
Coal  oil,  88 

Coalinga,  California,  oil  field,  444 
Cody  anticline,  Wyoming,  407 
Coefficients  of  expansion  of  oil,  71 
Coke  from  petroleum,  uses  of,  3 
Cold  Bay,  Alaska,  oil  field,  472 
Colloidal  matter  in  clays,  58 

effect  on  porosity,  44 
Colmar,  Illinois,  oil  field,  161,  266 
Colombia  oil  fields,  581 

oil  seeps,  23 
Color  of  petroleum,  68 
Color  of  rocks  as  expressed  in  well 

logs,  103 

Colorado  oil  field,  429 
Colorado  oil  shales,  30 
Comodoro  Rivadavia,  Argentina,  oil 

field,  56,  591 

Composition  of  natural  gas,  74 
Composition  of  petroleum,  71 
Compression  method  of  gas  recovery, 

77 
Concentration  of  water  in  oil  sands, 

186 
Contour  maps,  96 

method  of  making,  97 

of  anticline,  98 
Convergence  sheet,  220 
Cook  Springs  fault,  Texas,  347 
Copalite,  17 
Copper  Mountain,  Wyoming,  oil  in 

granite  of,  58 
Corsicana,  Texas,  gas  of,  34,  49,  339 


Covering  strata 

kind  of,  65 

strength  of,  66 

thickness  of,  66 

Coyote  oil  field,  California,  466 
Crawford  County,  Illinois,  oil  fields, 

261 

Cretaceous  oils,  nitrogen  in,  82 
Crimea,  Russia,  oil  fields,  543 

folds  of,  169 
Criner  Hills,  276 
Crystalline  hydrocarbons,  17 
Crystallization,  force  of,  372 
Cuba,  oil  occurrences,  571 

reservoir  rocks,  57 

clay  in,  59 
Curves  showing  oil  well  production, 

186 
Gushing  field,  Oklahoma,  287 

oil  sand  of,  61 

sections  of,  105,  156,  169 


Daly's  hypothesis  of  oil  accumula- 
tion, 167 

Damon  Mound,  Texas  oil  field,  370 

Day's    Experiments    on    Fraction- 
ation,  117 

Dayton,  Texas,  oil  field,  370 

De  Deque,  Colorado,  oil  field,  155. 
432 

Decline  of  oil  wells,  186 

Decomposition  of  cellulose,  85 

Deep  wells  of  Appalachian  region, 
map  showing,  220 

Deformation  of  petroliferous  strata, 
170 

Delaware  limestone,  Ontario,  oil  in, 
476 

Density  of  oil,  69 

Deposition  of  salt,  in  casings,  52 
in  oil-bearing  strata,  52 

Depressed  structural  features,  oil  in, 
124 

Derbyshire,  England,  oil  field,  507 
reservoir  rock,  55 

Desdemona,  Texas,  field,  334 


598 


INDEX 


De  Soto-Red  River  field,  Louisiana, 

131,  355 

Devol  anticline,  Oklahoma,  348 
Devonian  in  Appalachian  fields,  220 
Diastrophic  theory  of  oil  accumula- 
tion, 109 

Diatom,  composition  of,  86 
Diatomaceous  shale,  86 
Diatomin,  86 
Dikes  of  bitumen,  29 
Dikes,  relation  of,  to  oil  accumula- 
tions, 152 
Dip  and  strike,  96 
Dip  chart,  100 

Distances  covered  by  migrating  oil,  1 62 
Distribution  of  petroleum,  6 
Dolomite  of  Trenton  oil  field,  59 
Dolomitization  of  limestone,  effect  on 

porosity,  45 
Domes,  accumulation  of  oil  on  sides 

of,  139 

oil  reservoirs  on,  120,  123 
Dos  Bocas  well,  Mexico,  50,  184 
Douglas,  Wyoming,  oil  field,  377,  386 
Dover  West,  Ontario,  oil  field,  482 
Drake  well,  Pennsylvania,  66 
Drilling  in,  by  expelling  sand,  183 
Drip  gasoline,  78 
Dry  gas,  35 
Dry  sand,  48 

Duke-Knowles,  Texas,  oil  field,  63,  334 
Duncan,  Oklahoma,  oil  field,  322 
Dundee    formation,    Michigan,    salt 

water  in,  49 

Dunville,  Wisconsin,  sandstone,  poro- 
sity of,  42,  61 
Dutch  East  Indies,  oil  production 

of,  5 

Dynamic    metamorphism    of   petro- 
leum, 173 

Dynamo-chemical    processes    in    oil 
formation,  84 

E 

East  Indies  oil  fields,  553 
production  of,  5 
resources  of,  11 


Eastland  County,  Texas,  map  of,  334 
East  Texas  oil  fields,  346 

salt  water  in,  49 
Ebano,  Mexico,  oil  field,  504 

structure  of,  136 
Echigo,  Japan,  oil  fields,  568 
Ecuador  oil  fields,  590 
Eddy  County,  New  Mexico,  oil  field, 

439 
Edge  water,  undulating  surface  of, 

162 
Edgmont  oil  region,   New  Zealand, 

569 
Egypt,  oil  fields  of,  549 

oil  production,  5 

oil  seeps  in,  22 

probable  production  of,  11 

salt  water  in,  50 
Elaterite,  17 

Elbing,  Kansas,  oil  field,  314 
Eldorado,  Kansas,  oil  field,  313 

amplitude  of  dome,  133 
Electra,  Texas,  field,  324 
Elevated  structural  features,  oil  IL, 

123 

Elgin,  Texas,  field,  338 
Elk  Basin,  Wyoming,  field,  404 
Elm  Grove,  Louisiana,  field,  350 
Elysian  Park,  California,  oil  field,  464 
Embar  limestone,  Wyoming,  oil  in, 

389 

Emilia,  Italy,  oil  field,  515 
Engler's  method  of  oil  analysis,  73 
Engler's  viscosimeter,  71 
Epochs,  petroleogenic,  190 
Erin,  Trinidad  Island,  mud  volcanoes 

of,  37 

Errors  in  logs,  103 
Esthonia,  black  shale  forming  near 

coast  of,  87 

Ethane,  properties  of,  72 
Ether,  uses  of,  3 
Eurasia,  petroleogenic  provinces  of, 

192 

Europe,  map  showing  structural  axes, 
517 

oil  fields  of,  507 
Evangeline  dome,  Louisiana,  371 


INDEX 


599 


Evaporation  of  salt  water  in  oil  wells, 

186 

Expansion  of  oil  due  to  heat,  71 
Experiments,  on  capillary  attraction 

in  sands,  113 
,  on  oil  accumulation,  111 
relating  to  origin  of  oil,  80,  83 


F 


Fault  traps,  136 

Faulting  of  reservoirs,  170,  171 

Faults,  asphalt  in,  171 

Faults  in  Interior  Lowlands  of  United 

States,  205 

Faults,  reservoirs  sealed  by,  146 
Ferghana,  Turkestan,  oil  fields,  22, 

546 
Fergus  County,  Montana,  oil  fields 

of,  411 
Fichtelite,  17 

Findlay,  Ohio,  gas  seeps  at,  20 
Fire  damp,  33 
Fissures,  as  oil  reservoirs,  47,  156 

in  dolomite,  59 

oil  in,  124 

with  bitumens,  47 
Fixed  carbon  in  coals,  relation  to  oil 

pools,  173 
Flat  lying  beds  containing  oil  pools, 

123 

Flatrock  pool,  Oklahoma,  297 
Florence,  Colorado,  oil  field,  429 

character  of  reservoir  rock,  55, 

157 

Florence,  Kansas,  oil  field,  314 
Flow  of  oil  by  heads,  184 
Folds,  164 

behavior  with  depth,  165 

developed  above  faults,  167 
Force  of  crystallization,  46,  373 
Formosa  oil  fields,  568 

oil  production,  4 

oil  resources,  11 
Fort  Smith,  Arkansas,  gas  fields,  301 

reservoir  rock  of,  54 
Eountains  of  oil,  183 
Fowlkes,  Texas,  field,  324 


Fox,  Oklahoma,  field,  321 
Fractionation  of  petroleum  in  clay, 

117 
Fracturing,  effect  on  oil  reservoirs, 

171 

France,  oil  fields  of,  509 
Fredonia,  Kansas,  oil  field,  314 
Freemont    County,     Wyoming,    oil 

fields,  389 

Fresno  County  fields,  California,  444 
Fuller's  earth,  effect  on  oil  of,  117 
Fullerton,  California,  oil  field,  466 
Furbero,  Mexico,  oil  field,  506 
reservoir  rocks  of,  57 


Galatea  Point,  Trinidad,  oil  seeps,  25 
Galicia  oil  fields,  517 

production  of,  4 

resources  of,  11,  55,  56 

salt  water  in,  50 

structures  of,  130 
Galicia,  oil  springs  of,  21 
Garber  field,  Oklahoma,  300 
Garfield  County,  Oklahoma,  oil  fields, 

300 
Gas  accumulations,  cause  of  flows  of 

oil  by  heads,  184 
Gas,  analyses  of,  34 

association  with  oil,  33 

composition  of,  75 

composition   of  that  associated 
with  oil,  35 

evidences  of,  36 

in  bitumen  mines,  31 

origin  of,  1 
Gas  pressure,  180,  182 

effect  on  oil  accumulation,  112 

importance  in  oil  recovery,  183 

relation  to  depth,  181 
Gas  seeps,  33 

Gas,  use  of  in  increasing  oil  produc- 
tion, 189 

waste  of,  effect  on  oil  produc- 
tion, 183 

Gas  wells,   cause  of  change   to   oil 
wells,  184 


600 


INDEX 


Gas  wells,  in  fissures,  behavior  of,  158 
Gas,  wet,  34 

Gaseous  hydrocarbons,  17 
Gasoline,  content  in  wet  gas,  212 

uses  of,  3 
Gaspe,  Quebec,  oil  fields,  484 

oil  seeps,  23 
Geary  well,  224 
Gebel  Zeit,  Egypt,  22 
Geochemical  processes  in  oil  forma- 
tion, 84 
Geological  age  of  petroleum  bearing 

strata,  11,  12 

Geological  map  of  United  States,  197 
Georgia,  oil  prospects  in,  362 
Geothermal  gradient,  94 
Germany,  oil  fields  of,  513 

production  of,  4 
Geyser-like  flows  of  oil  wells,  cause 

of,  184 
Gilsonite,  17 
Gilsonite  dikes,  Uinta  basin,  Utah,  26 

origin  of,  31 

Glenmary  oil  field,  Tennessee,  246 
Glenn  pool,  Oklahoma,  292 
Goff  well,  log  of,  222 
Grahamite,  17 

dike,  Ritchie  County,  West  Vir- 
ginia, 19,  26,  29 

Grandfield  area,  Oklahoma,  348 
Granite,  oil  in  fractures  of,  58 

in  Kansas,  309 
Grass  Creek  oil  field,  Wyoming,  407 

salt  water  in,  51 
Gravitational  arrangement  of  oil  and 

water,  105 
Gravity  of  oil,  69 
Great  Britain,  oil  fields  of,  507 
Greater  stresses  as  causes  of  open- 
ings, 47 

Greenville,  Illinois,  gas  field,  266 
Greybull  dome,  Wyoming,  404 
Groesbeck  gas  pool,  Texas,  342 
Grosny,  Russia,  oil  field,  541 

section  of,  134 

seepages,  134 

Gulf  coast  oil  fields  of  United  States, 
365 


Gulf  of  Mexico,  oil  ponds  of,  25 

Gum  beds,  Ontario,  27,  247 

Gumbo,  103 

Gum  oil,  Ontario,  19,  477 

Gusher  Bend  fault,  Louisiana,  171, 

338 

Gushers,  183 

Gypsum,  behavior  in  drilling,  102 
in  oil  fields,  91 


H 


Haiti,  oil  occurrences  in,  573 

Hand  dug  wells,  6 

Hanksville,    Utah,    oil    occurrences 

near,  435 

Hannover  oil  fields,  Germany,  513 
Hard  beds,  use  of  term  by  drillers,  102 
Hardstoft  well,  Derbyshire,  England, 

508 

Harris  County,  Texas,  oil  field,  370 
Hartford,  Tennessee,  oil  field,  244 
Hartite,  17 

Hatchetigbee  fold,  Alabama,  361 
Hatchettite,  17 
Healdton,  Oklahoma,  oil  field,  320 

map  of,  124 

stereogram  of,  125 
Heat  gradient  in  oil  fields,  92 
Heaving  sand,  definition,  104 
Helium  in  natural  gas,  33,  82 
Henrietta,  Texas,  oil  field,  326 
Hoeing  sand,  oil  in,  161 

photograph  of,  61 
Holy  Island,  Russia,  oil  fields  of,  543 

bone  deposits,  27 

gas  seeps,  6,  35 

mud  volcanoes,  22 

reservoir  rocks,  56 

salt  water,  50 

structure  of,  130 
Homer,  Louisiana,  oil  fields,  350 
Hominy  pool,  Oklahoma,  297 
Hot  salt  springs,  22 
Humble,  Texas,  oil  field,  370 
Hundred  foot  sand,  pay  streaks  in, 

114 
Huntley  field,  Montana,  415 


INDEX 


601 


Hurgada  oil  field,  Egypt,  522 

Hydraulic  theory  of  oil  accumulation, 
109 

Hydrogen  sulphide  in  oil,  elimina-. 
tion  of,  68 

Hydromotive  theory  of  oil  accumula- 
tion, 109 


Irvine,  Kentucky,  salt  water  in,  49 

shallow  wells  of,  67 

structure  of,  144 
Isovol,  definition  of,  174 
Italy,  oil  fields  of,  514 

production  of,  4 


Idaho,  oil  occurrences  in,  441 
Igneous  dikes,  relation  to  reservoirs, 

140 

Igneous  intrusions,  oil  fields  near,  152 
Igneous  rocks  in  Interior  Lowlands 

of  United  States,  204 
Igneous  rocks,  oil  in,  124 
Illinois  oil  fields,  256 

reservoir  rocks  of,  54,  56 

salt  water  in,  49 

structure  of,  125 
Impsonite,  17 
Inclination  necessary  for  movement 

of  oil,  163 
Increasing  oil  production,   methods 

for,  189 
India,  oil  production  of,  5 

oil  resources,  11 
Indiana  oil  fields,  288 

reservoir  rocks  of,  53 
Indications  of  oil,  16 
Iniskin  Bay,  Alaska,  oil  near,  472 
Inorganic  theories  of  origin  of  oil,  80 
Intergranular  spaces  in  rocks,  42 
Interior  Lowlands  of  United  States, 
198 

igneous  rocks  in,  204 

structure  of,  198 
lola,  Kansas,  oil  fields,  312 
Iowa  Park,  Texas,  oil  field,  324 
Iron  oxide  films,  detection  of,  24 
Irrawady  River  oil  fields,  Burma,  554 

dug  wells  of,  22 

oil  seeps  of,  22 

salt  water  in,  50 
Irvine,  Kentucky,  oil  field,  241 

dolomite  of,  59 

faulting  in,  171 


Jackson  area,  Mississippi,  oil  pros- 
pects near,  359 
Jackson  fold,  Alabama,  361 
James  Bay,  Canada,  oil  seep  near,  475 
Japan,  oil  fields  of,  566 

production  of,  4 

reservoir  rock  of,  56 

resources,  11 

seeps,  23 

Java,  oil  fields  of,  559 
Jemsa,  Egypt,  oil  field,  552 
Jennings,  Louisiana,  oil  near,  371 
Jessamine  dome,  Kentucky,  235 
Jigging  action  in  rotary  drilling,  103 
Joplin  zinc  district,  bitumen  in,  18 
Jujuy  oil  field,  Argentina,  591 


K 


Kansas  oil  fields,  307 

gas  pressure  in,  181 

reservoir  rocks,  53 

salt  water  of,  49 
Katalla  oil  field,  Alaska,  470 
Kay  County  pools,  Oklahoma,  298 
Kentucky  oil  fields,  233 

reservoir  rocks,  53 

solid  bitumens,  27 

structure  of,  205 

Kern  River  oil  field,  California,  457 
Kerogen,  87,  88 
Kerosene,  uses  of,  3 
Kertch  oil  field,  Russia,  543 

mud  volcanoes  of,  37 
Kimmeridge  clays,  England,  inflam- 
mable nature  of,  39 
King's  County,  California,  oil  fields, 

444 
Kir,  6 


602 


INDEX 


Klias  Peninsula,  Borneo,  mud  vol- 
canoes of,  37 

Knox  County,  Kentucky,  oil  fields, 
243 

Krosno,  Galicia,  oil  field,  524 

Kutei,  Borneo,  oil  field,  560 


La  Barge  field,  Wyoming,  396 

La  Brea,  6 

La  Brea  Mountain,  Peru,  581 

La  Brea,  Trinidad  Island,  575 

Lacustrine  deposits,  gas  in,  33 

Lake  Ainslee,  Nova  Scotia,  oil  seeps 

in,  483 

Lake  Basin,  Montana,  411 
Lake  Dauterine,  paraffin  dirt  near,  36 
Lake     Maracaibo,     oil     occurrences 

near,  580,  582 
Lambton  County,  Ontario,  oil  fields 

of,  476 

salt  water  in,  49 
structure  of,  123 
Lander  oil  field,  Wyoming,  389 
La  Salle  anticline,  Illinois,  262 
Lawrence  County,  Illinois,  oil  fields, 

261 

Lawton,  Oklahoma,  oil  field,  322 
Lenses  of  sand  in  reservoirs,  142 
Lethal  gases  in  oil  fields,  33 
Lethbridge,  Canada,  gas  near,  491 
Lias  clays  of  England,  inflammable 

nature  of,  39 
Lidah  oil  pool,  Java,  559 
Life  of  oil  wells,  186 
Lignite,  definition,  104 

association      with      oil-bearing 

strata,  88 

Lima-Indiana  oil  field,  248 
reservoir  rocks,  56 
salt  water  of,  49 
structure  of,  120 
Limmer,  Germany,  asphalt  deposit, 

514 
Lires  Valley,  Italy,  asphalt  deposits, 

515 
Litchfield,  Illinois,  oil  field,  265 


Llano-Burnett  region,  Texas,  277 

Llewellyn  well,  West  Virginia,  66 

Lobitos,  Peru,  oil  field,  588 

Loco,  Oklahoma,  oil  field,  321 

Logs  of  oil  wells,  101 

Lompoc,  California,  oil  field,  458,  462 

oil  seeps  of,  27 

Lost  Hills,  California,  oil  field,  449 
Lost  Soldier  field,  Wyoming,  392 
Louisiana  oil  fields,  Gulf  Coast,  365 
Louisiana  oil  fields,  northwestern,  346 

salt  water  in,  49 

structure  of,  1-26 
Lucas  well,  Texas,  368 
Lusk,  Wyoming,  oil  field,  394 


M 


Macon,  Georgia,  geology  near,  363 
Madill,  Oklahoma,  oil  field,  324,  325 

unconfor    ;ty  at,  150 
Madoera  Islan    oil  field,  560 
Magdalena    valley,     Colombia,     oil 

fields,  582 
Maidan-i-Naphtun,  Persia,  oil  field, 

548 
Maikop,  Russia,  oil  field,  542 

relation  to  structure,  140,  150, 

151 

Majella,  Italy,  asphalt  near,  516 
Maltha,  1,  17 
Manjak,  20,  572 
Mapping  oil  bearing  strata,  100 
Marine    organisms    in    concentrated 

salt  solutions,  90 
Marsh  gas,  33,  75 
Martha  O.  Goff  well,  221 

log  of,  222 
Maverick  Springs,  Wyoming,   field, 

389 

McClosky  sand,  Illinois,  261 
McCoy's  experiments,  113 
McKittrick  oil  field,  California,  450 

oil  reservoirs  at  unconformity, 
150 

section  of,  155 

Medicine  Hat,  Canada,  gas  near,  491 
Mendez  formation,  Mexico,  oil  in,  499 


INDEX 


603 


Mendoza,  Argentina,  oil  field,  591 
Menifee,  Kentucky,  gas  field,  240 
Mesopotamia  oil  fields,  546 

oil  resources,  11 

oil  seeps,  22 

Metamorphism  of  oil  in  rocks,  173, 
176 

importance  of  cover,  179 
Methane,  33,  72 

Mexia-Groesbeck    gas    field,    Texas, 
342 

gas  of,  34 

porosity  of  sand,  62 
Mexico  oil  fields,  129 

probable  future,  11 

production  of,  5 

salt  water  in,  50 

structure  of,  152 
Miarolitic  cavities,  45 
Michigan  oil  fields,  254 

reservoir  rock,  53        inr 
Middlesex  County,  Ontari  'xoil  fields, 

164 

Midway,  California,  syncline,  51 
Midway  oil  field,  California,  454 
Migration  of  oil,  distance  covered, 

162 

Migration  of  oil,   inclination  neces- 
sary for,  164 
Minasragra,  Peru,  bitumen  in  veins 

of,  26 
Minnesota,  gas  in  lacustrine  deposits 

of,  33 

Mississippi  Embayment,  349 
Mississippi,  prospects  of,  358 
Missouri,  oil  field,  54,  314 
Monoclines,  oil  pools  on,  123,  140 

sealed  by  faulting,  144 

sealed  by  intrusions,  152 
Monroe  gas  field,  Louisiana,  350 
Mons  Petrolius,  22 
Montana  oil  fields,  409,  420,  426 
Moorcroft  field,  Wyoming,  392 
Moreni,  Rumania,  oil  field,  529,  531 
Morris,  Oklahoma,  district,  303 
Mosa  township,    Ontario,   oil   field, 

476,  481 
Mosby,  Montana,  oil  field,  410 


Mosul,  Turkey,  oil  occurrence  in,  546 

Mounds,  33 

Mountainward  folds,   oil  accumula- 
tions on,  137 

Mud  dikes,  38 

Mud-laden  fluid,  use  of  in  drilling, 
102 

Muds,  pore  spaces  of,  41 

Mud  volcanoes,  33 
of  Idaho,  441 
origin  of,  36 

Mule  Creek,  Wyoming,  394 

Munn's  hypothesis  of  oil  accumula- 
tion, 109 

Muskogee    County,    Oklahoma,    oil 
fields,  300 

Mussellshell    valley,    Montana,    oil 
prospects  of,  418 


N 


Nacotosh  sand,  62,  350 
Naphtha,  17 

uses,  3 
Natural  gas,  definition,  1 

composition,  76,  77 

recovery  of  gasoline  from,  77 
Neft,  6 

Negritos,  Peru,  oil  field,  588 
Neodesha,  Kansas,  section  of  rocks  iu 

well,  312 

Nesson,  North  Dakota,  anticline,  428 
Netherlands  India,  oil  fields,  553 

oil  production  of,  5 
Neuquen,  Argentina,  oil  field,  591 
New  Brunswick,  Canada,  oil  and  gas 
fields,  483 

oil  shale,  39 

Newcastle,  Wyoming,  oil  field,  393 
Newfoundland  oil  seeps,  23,  495 
New  Iberia,  Louisiana,  oil  field,  371 

paraffin  dirt  of,  36 
Newkirk,  Oklahoma,  oil  field,  298 
New  Mexico  oil  fields,  439 
New   Plymouth,   New   Zealand,   oil 

field,  569 

New  South  Wales,  oil  shale  of,  39 
New  York,  gas  pressure  in,  180 


604 


INDEX 


New  Zealand  oil  fields,  568 

Nigrite,  17 

Nitrogen  compounds  in  petroleum, 
39,81 

Nodes  on  anticlines,  accumulation  of 
oil  on,  137 

North  America,  petroliferous  prov- 
inces of,  192 

North     Casper     Creek,     Wyoming, 
anticline,  392 

North  Dakota,  gas  fields  of,  428 

North  Texas,  isovol  map  of,  177 

North  Island,  New  Zealand,  oil  field, 
569 

Nova  Scotia,  Canada,  oil  seeps  of,  483 
bituminous  dike  of,  30 
oil  shale  of,  30 

Nowata  County,  Oklahoma,  295 


Odor  of  petroleum,  tests  for,  68 

Oelheim  oil  field,  Germany,  513 

Ohio,  Clinton  gas  field  of,  142 

Ohio,  eastern  oil  fields  of,  225 
reservoir  rocks,  53 
salt  water  in,  48 

Ohio,  western  oil  fields  of,  See  Luna- 
Indiana  oil  field 

Oil  accumulation  in  sands  of  irregu- 
lar pore  space,  159 

Oil  blanket,  undulating  base  of,  138, 
163 

Oil  City,  Pennsylvania,  porosity  of 
oil  sand,  62 

Oil  Creek,  Pennsylvania,  19 

Oil,  definition,  1 

Oil    fields,    tables    showing    salient 

features  of,  118 
waters  of,  48 

in  California,  51 

Oil  in  basalt,  57 

Oil    in    fractured    granite,    Copper 
Mountain,  Wyoming,  58 

Oil  in  igneous  rocks,  57 

Oil  Mountain,  Wyoming,  anticline, 
392 

Oil  ponds,  25 


Oil  recovery,  180 

Oil  reserves,  methods  of  estimating, 

186,  188 
Oil  sands,  "feel"  of,  60 

outcrop,  character  of,  60 

tests  for,  260 

use  of  term  by  drillers,  102 
Oil  seeps,  16,  22,  503 
Oil  shale,  amount  of  oil  in,  38 

Colorado,  30 

compression  of,  38 

Green  River,  30 

Nova  Scotia,  30 

oil  in,  38 

Utah,  30 

Oil  Springs,  18,  27 
Oil  Springs,  Alleghany  County,  New 

York,  24 

Oil  Springs    Dome  of  Ontario,  122, 
477,  479 

section  of,  66 
Oil,  tests  for,  28 
Oil  wells,  change  to  water  wells,  184 

decline  of,  186 

flow  by  heads  of,  184 

in  fissures,  behavior  of,  157 

life  of,  186 
Oklahoma  oil  fields,  274,  279 

gas  pressure  of,  181 

grahamite  dikes,  30 

isovol  map  of,  176 

oil  in  shale,  38 

reservoir  rocks,  53 

salt  water  in,  49 

solid  bitumens,  27,  30 

structure  of,  126 
Okmulgee,  Oklahoma,  oil  fields,  303, 

304 

Old  Sunset,  California,  sulphur  de- 
posit of,  148 
Olefine  series,  72 
Olinda,  California,  oil  field,  466 
Onondaga,  oil  in,  Canada,  476 
Ontario  oil  fields,  476 

reservoir  rocks  of,  55 

sections  of,  66 

structure  of,  122,  129 
Opaka,  Galicia,  oil  field,  523 


INDEX 


605 


Openings  in  rocks,  41 
Oregon  Basin,  Wyoming,  oil  field,  407 
Oregon,  oil  prospects  of,  441 
Organic  theory  of  origin  of  petroleum, 

83 

Origin  of  anticlines,  134 
Origin  of  gas,  80 
Origin  of  petroleum,  8Q 
Orographic  element,  definition  of,  195 
Osage  County,  Oklahoma,  oil  field, 
297 

accumulation  on  domes,  139 
Ouachita  Mountains,  275 

structure  of,  198 
Overturned  folds,  134 

effect  of,  on  oil  reservoirs,  170 
Ozark  axis,  201,  204 
Ozark  Plateau,  198 
Ozark  Uplift,  272 
Ozokerite,  17,  31 


Pacific    coast    oil    fields    of    United 

States,  442 

Packed  sand,  definition  of,  104 
Paleozoic  oils,  nitrogen  in,  82 
Pangalan,  Sumatra,  oil  field,  558 
Paraffin,  3 
Paraffin  dirt,  16,  36 
Paraffin  oils,  73 
Paraffin  series,  72 
Paraffin  wax  in  well  casings,  186 
Parallel  folds,  164 

Paritutu,  New  Zealand,  oil  field,  569 
Payette,  Idaho,  oil  prospects,  441 
Pay  streaks  in  Sewickley  quadrangle, 

Pennsylvania,  114 
Peabody,  Kansas,  oil  field,  314 
Pechelbronn,  Alsace,  oil  field,  61,  510 

oil  spring,  21 
Pecos  valley,  New  Mexico,  oil  field, 

440 

salt  water  in,  50 

Pelican,  Louisiana,  oil  field,  350,  355 
Pelican  Rapids,  Canada,  gas  field,  491 
Pemberton    well,     Glenmary,    Ten- 
nessee, 247 


Pennsylvania,  oil  fields,  206 
Pennsylvania     petroliferous     strata, 
conditions  of  formation,  89 
Pentane,  72 

Periodic  flow  of  oil  wells,  184 
Permeability  of  rocks,  effect  of  clay 

and  colloids  on,  44 
Persia  oil  fields,  547 

oil  resources  of,  11 
Peru,  oil  fields  of,  584 

bone  depsits,  27 

oil  ponds,  25 

oil  production,  5 
Peru,  Kansas,  oil  field,  structure  of, 

154 

Petchora  River  oil  field,  Russia,  533 
Petroleogenic  epochs,  190 
Petroleum,  see  Oil 

Petroleum,  accumulation  in  consoli- 
dated rocks,  2 

in  unconsolidated  rocks 
Petroleum  bacteria,  40 
Petroleum  blanket,  base  of,  163 
Petroleum,  composition  of,  71 

definition,  1 

derivation  of,  from  oil  shales,  38 

distances  of  movement  of,  63 

distillation  of,  2 

distribution  of,  6 

future  production  of,  7 

general  character  of  reservoirs  of  ,2 

general  occurrence,  1 

in  igneous  rocks,  57 

in  schists,  58 

Petroleum,  Kentucky,  oil  field,  244 
Petroleum,  local  origin  in  some  fields, 
163 

origin  of,  1,  80 

Petroleum,    production    of    Eastern 
hemisphere,  7 

Northern  hemisphere,  7 

refining  of,  2 

reserves  of,  10 

Southern  hemisphere,  7 
Western  hemisphere,  7 
Petroleum  sands,  character  of  out- 
crop, 60 

tests  for,  60 


606 


INDEX 


Petroleum  sands,  uses,  2 

wells  in  fissures,  behavior  of,  157 

world's  production,  4,  5 
Petrolia,  Ontario  oil  field,  477,  479 
Petrolia,  Texas  gas  field,  34,  122,  326, 

328 

Petroliferous  provinces,  190,  192 
Petroliferous  strata,  deformation  of, 
170 

geothermal  gradient  in,  94 
Philippine  Islands,  asphalt  in,  23 
Philippine  Islands,  oil  occurrences  of, 

561 
Placerita  Canyon  oil  field,  California, 

461 
Physiographic     provinces     of     the 

United  States,  195 
Pilot  Butte,  Wyoming,  392 
Pine  Dome,  Wyoming,  392 
Pitch  Lake,  Trinidad  Island,  21,  25, 
575 

composition  of  asphalt  of,  26 
Pittsburg  coal,  use  of  as  key  bed,  208 
Plant  remains  in  oil  formation,  84 
Poison   Spider   anticline,   Wyoming, 

392 

Poncha  City  oil  field,  Oklahoma,  298 
Popo  Agie  dome,  Wyoming,  389 
Porcupine  Dome,  Montana,  415 
Porosity  of  granite,  45 

of  limestone,  64 

of  sands,  42 

Port  Huron  oil  field,  Michigan,  294 
Portrero  well,  Mexico,  498 
Poteau  gas  field,  Arkansas,  306 
Potok,  Galicia,  oil  field,  385 
Powell  field,  Texas,  339 
Prahova,  Rumania,  oil  field,  529 
Pressure  of  gas,  180 

in  sand  lenses,  181 
Primary  openings  in  rocks,  42 
Production  in  oil  wells,  186 
Propane,  72 

Properties  of  petroleum  and  gas,  68 
Provinces,  petroliferous,  190 
Puente  Hills,  California,    oil    fields, 

466 
Pumice,  openings  in,  44 


Q 


Quebec,  Canada,  oil  fields  of,  484 
Queensland,  Australia,  gas  field  of, 

569 

Quicksand,  definition  of,  103 
Quicksilver  veins,  bitumens  in,  26 


Ragland,  Kentucky,  oil  field,  433 

Rainbow  of  oil,  24 

Rangely,  Colorado,  oil  field,  433 

Ranger,  Texas,  oil  field,  335,  337 

Records  of  wells,  101 

Recovery  of  oil,  estimates  by  Wash- 

burne's  method,  63 
Red  beds  in  oil  fields,  91 
Red  River  fault  zone,  347 
Red  River  oil  field,  Louisiana,  126, 

131 
Red  River  oil  field,  Oklahoma  and 

Texas,  316,  324 
Red  shales,  in  petroliferous  areas,  90 

dehydration  of  iron  in,  by  salt,  91 
Rembang,  Java,  oil  field,  559 
Reservoir  rocks,  53 

mineral  composition  of,  58 
Reservoirs  of  oil,  age  of,  14,  15 

faulting  of,  170 

formed  by  faults,  140 

formed  by  fissures,  156 

in  synclines,  154 

on  monoclines,  139 
Resinous  hydrocarbons,  17 
Rhine  valley,  oil  fields  of,  511 
Rivadavia,  Argentina,  55,  591 
Rivanozanna,  Italy,  oil  prospects,  515 
Robinson  oil  pool,  Illinois,  262 
Rock  classification,  104 
Rock  gas,  1 
Rock  oil,  1 

definition  of,  1 

See  Petroleum 

Rock  powder,  pore  space  of,  41 
Rock  River,  Wyoming,  oil  field,  392 
Rock  systems  of  the  United  States, 
196 


INDEX 


607 


Rocky  Mountains  of  United  States, 

oil  fields  of,  128,  375 
Rogi,  Galicia,  oil  field,  524 
Rorquada,  Egypt,  oil  field,  552 
Rotary  drilled  wells,  102 
Rough  Creek,  Kentucky,  uplift,  201 
Rowne,  Galicia,  oil  field,  524 
Rumania,  oil  fields  of,  525 

mud  volcanoes,  21 

oil  springs,  21 

production  of,  4 

reservoir  rocks  of,  55,  56 

resources  of,  11 

salt  water  in,  50 
Russia,  oil  fields  of,  533 

production  of,  4 

resources  of,  11 

salt  water  in,  50 

structures  of,  130 


Sabine  Uplift,  Louisiana,  348,  350 
Sabunchy,  Russia,  oil  field,  540 
Sakhalin,  oil  resources,  11 
Salient  features  of  oil  fields,  118 
Salt  beds,  deformation  of,  137 

in  oil  fields,  91 

Salt  Creek,  Wyoming,  oil  field,  127, 
157,  382 

map  of,  127 

ozokerite  of,  32 

section  of,  131 
Salt  domes,  136 

gas  seeps  of,  20 

Gulf  coast  of  United  States,  369 

of  Rumania,  136 

origin  of,  46,  136 

section  of,  136 

Salt  Lake  oil  field,  California,  466 
Salt  Lake,  Utah,  oil  occurrences  in, 

435 

Salt  licks,  39 
Salt  seeps,  39 
Salt  water,  in  petroliferous  strata,  48 

association  with  oil,  48 

origin  of,  1 
Salt  water  seeps,  39 


Salta  oil  field,  Argentina,  591 
Salting  up  of  gas  wells,  186 
San  Domingo,  oil  resources  of,  573 
San  Filipe  formation,  Mexico,  oil  in, 

499 
San     Joaquin     valley,     California, 

waters  of,  51 
San  Luis  Obispo,  California,  oil  field, 

462 
Sand,  cementation  of,  186 

in  oil,  38,  183 

Sand,  lenses  as  oil  reservoirs,  142 
Sandoval  oil  field,  Illinois,  268 
Santa   Barbara   County,   California, 

oil  fields,  462 

Santa  Clara,  California,  oil  field,  458 
asphalt  in,  172 
burnt  oil  shale  of,  39 
Santa  Cruz  asphalt  deposits,   Cali- 
fornia, 172 

Santa  Elena,  Ecuador,  oil  field,  590 
Santa  Maria,  California,  oil  field,  462 
Santander,  Colombia,  oil  fields,  582 
Saratoga,  Texas,  oil  pool,  370 
Sarawak,  Borneo,  oil  field,  561 
Saybolt  viscosimeter,  71 
Schists,  oil  in,  124 
Schodnica,  Galicia,  oil  field,  523 
Schwabweiler  oil  field,  France,  509 
Scotland,  Georgia,  oil  prospects  of, 

362 

Secondary  openings  in  rocks,  42 
Segregation    of    oil    and   water    by 

capillary  action,  112 
Sewickley  quadrangle,  Pennsylvania, 

oil  fields  of,  114 
Shale  gas,  158 

Shannon,  Wyoming,  oil  pool,  384 
Shell,  definition  of,  103 
Shell  rock,  definition  of,  104 

porosity  of,  44 
Shore  conditions  during  formation  of 

oil,  87 
Shreveport,    Louisiana,   analyses   of 

gas  of,  34 

Shrinkage  cracks,  45 
Shut  off  wells,  behavior  of,  184 
Sicily,  oil  fields  of,  517 


608 


INDEX 


Similar  folds,  164 

Singu  oil  field,  Burma,  555 

Slate,  102 

Slichter's  experiments  on  porosity,  43 

Soapstone  as  covering  strata,  66 

Solid  bitumens,  25 

above  anticlines,  32 
origin  of,  26 
Solution  cavities,  45 
Sour  Lake  oil  field,  Gulf  coast,  370 

acid  water  of,  40 
South  America  oil  fields,  580 

estimate  of  probable  production, 

11 
South  Casper  Creek,  Wyoming,  oil 

prospects,  392 
Spanish  Lake,  Louisiana,  paraffin  dirt 

near,  36 

Spheres,  pore  space  between 
Spindletop  oil  field,  Texas,  365 
section  of,  136 
sulphur  of,  35 
Spotted  sands,  oil  accumulation  in, 

159 

Spouters,  183 

Spring  Creek  district,  Tennessee,  244 
Spring  Valley  oil  field,  Wyoming,  396 
Spurrier,  Tennessee,  oil  field,  244 

salt  water  in,  49 

Stephens  County,  Texas,  oil  field,  334 
Stephensville,  Arkansas,  gas  field,  356 
Sticky  formations,  102 
Stillwater  Basin,  Montana,  oil  pros- 
pects of,  411 

St.  Francis  Mountains,  Missouri,  273 
Stony  Creek  gas  field,  New  Bruns- 
wick, 483 

St.  Peter  sandstone,  nature  of  out- 
crop, 66 

Strata  containing  oil,  kinds  of,  10 
Straw  colored  oil,  68 
Strawn,  Texas,  oil  field,  67,  334 
Strike  of  strata,  96 
Structural  features  of  oil  reservoirs, 

120 

Subcapillary  openings,  41 
Submarine  gas  seeps,  35 
Submarine  oil  sands,  eruptions  of,  25 


Submicroscopic  openings,  45 
Successions    of   petroliferous   strata, 

16i 

Succinite,  17 
Suez  oil  fields,  549 
Sulphur,  35 

in  gas,  40 

in  oil,  35,  86 

in  oil  bearing  strata,  85 

origin  of,  40,  148 
Sulphur  bacteria,  40,  85 
Sulphur  gases,  35 
Sumatra  oil  fields,  557 

coal  beds  and  petroliferous  strata 

of,  88 

Summerland,  California,  oil  field,  460 
Sun  River  area,  Montana,  421 
Sunset-Midway  oil  field,  California, 
451 

monocline  sealed  by  tar,  147 

sand  in  oil,  38 

size  of  grains  of  oil  sands,  63 

stereogram    showing    reservoirs, 

141 

Super  capillary  openings,  41 
Surakhany,  Russia,  gas  seeps,  21 
Surface  indications  of  oil,  16 
Sviatoi,  Russia,  oil  field,  543 
Swamp  gas,  analyses  of,  34 
Symbols  used  on  oil  field  maps,  99, 

196 

Symmetrical  folds,  133 
Synclines,  oil  reservoirs  on,  105,  124, 

154 

Systems  of  strata,  names  of,  196 
Szuchuan,  China,  oil  field;  568 


Tabasco  oil  field,  Mexico,  497 
Taber's  experiments  on  crystalliza- 
tion, 372 

Taft  gas  field,  Oklahoma,  303 
Taft  oil  field,  California,  456 
Taiwan,  oil  fields  of,  568 
Taman  Peninsula,  Russia,  oil  fields, 

543 
mud  volcanoes,  3 


INDEX 


609 


Tamasopa  limestone,  Mexico,  498 

porosity  of,  64 

Tamaulipas,  Mexico,  oil  fields,  497 
Tampico,  Mexico,  oil  fields,  5,  497 

oil  seeps,  26 

origin  of  reservoir,  135 

reservoir  rock,  55 

structure  in,  129 

Tarakan  Island,  Borneo,  oil  fields,  561 
Taranaki  oil  field,  New  Zealand,  569 
Tar  pits  of  Limmer,  Germany,  514 
Tar  sand  of  Athabasca  River,  27,  491 
Tar  sands,  reservoirs  sealed  by,  147 
Tar  spring  near  Miami,  Oklahoma,  18 
Taylor  marl,  oil  in,  343 

salt  water  in,  49 
Telfair  County,  Georgia,  oil  products 

of,  362 
Temperature,  effect  on  gravity,  110 

on  viscosity,  110 
Temperature,  in  oil  fields,  92 

of  Dos  Bocos  well,  110 
Tennessee  oil  fields,  244 
Terracesj  oil  in,  123,  153 
Tertiary  oil  fields,  deformation  of,  170 
Tertiary  oils,  nitrogen  in,  82 
Test  for  oil  in  rocks,  28 
Texas  oil  fields,  329,  330,  346,  365 
Thermal  gradient  in  oil  fields,  92 
Thiel's  experiments  in  oil  accumula- 
tion, 111 

Thornton,  Wyoming,  fields,  394 
Thrall,  Texas,  oil  field,  338,  343 

character  of  oil  reservoirs,  59 

reservoir  rocks,  57 

salt  water  in,  51 

section  of,  131 
Tiflis,  Russia,  oil  occurrences  near, 

545 

Tinawun  oil  pool,  Java,  559 
Titicaca,  Peru,  oil  field,  589 
Tolima,  Colombia,  oil  field,  583 
Topping  plants,  3 
Torchlight  dome,  Wyoming,  405 
Transcaspian  provinces,   Russia,   oil 

fields  of,  545 
Trenton  limestone  oil  fields,  248 

structure  of,  120 


Trenton  limestone,  oil  in, 

Illinois,  263 

Indiana,  253 

Ohio,  251 

Ontario,  476 

Trenton  limestone,  porosity  of,  64, 252 
Trinidad  Island  oil  fields,  21,  574 

porcelainite  of,  39 

production  of,  5 
Tubara,  Colombia,  oil  field,  592 
Tulsa,  Oklahoma,  oil  field,  292 
Turbaco,  Colombia,  oil  field,  582 
Tuxpam,  Mexico,  oil  fields,  497 


D 


Uinta  Basin,  fissures  in,  172 

gilsonite,  31 

oil  shales,  30,  38 
Uintaite,  17 
Unconformities,  monoclines  sealed  at, 

149 

Unconsolidated   materials,   deforma- 
tion of,  170 
United  States,  map  of,  197 

oil  production  of,  202 

probable  reserves,  11 
Unsymmetrical  folds,  133 
Upton-Thornton  field,  Wyoming,  394 
Urado,  Utah,  oil  field,  155,  434 

oil  spring,  24 
Urycz,  Galicia,  oil  field,  523 


Vacuum    method    of    increasing    oil 

production,  189 
Vale,  Oregon,  mud  volcanoes,  37 

oil  possibilities,  441 
Vanadium  veins,  bitumen  in,  26 
Veale  field,  Texas,  336 
Venango  oil  sands,  Pennsylvania,  48, 

120 

Venezuela  oil  fields,  580 
Ventura  County,  California,  oil  fields, 

458 

Vera  Cruz,  Mexico,  oil  fields,  497 
heat  gradient  of,  94 


610 


INDEX 


Vesicular    spaces    in    rocks    as    oil 

reservoirs,  44 
Vicksburg,  Mississippi,  oil  prospects, 

359 

Viking,  Canada,  gas  near,  491 
Virgin  City,  Utah,  oil  prospects,  439 
Viscosity  of  oil,  71 
Vivian,  Louisiana,  analyses  of  gas,  34 


W 


Wall     Creek    sand,    Wyoming,   61, 

382 

Warfield  anticline,  axis  of,  205 
Warm  Springs  dome,  407 
Warrior  coal  basin,  Alabama,  gas  in, 

247 

Washburne's  hypothesis  of  oil  segre- 
gation, 113 
Washburne's  method  of  estimating 

oil  reserves,  188 
Washington  County,  Oklahoma,  oil 

fields,  296 

Washinoki,  Japan,  oil  region,  568 
Water  in  oil  fields,  concentration  of 

salts  in,  186 
Water  in  oil  wells,  deposition  of  salt 

by,  93 

Water  sand,  104 
Wax,  deposition  of,  in  well  casings, 

186 
Wayne  County,  Kentucky,  oil  fields, 

243 

Weight  of  oil,  69 
Well  logs,  96,  101,  103 
Welsh,  Louisiana,  oil  field,  371 
West  Columbia  dome,  Texas,  370 
West  Virginia  oil  fields,  213,  217 

reservoir  rocks,  53 
Western  Canada  oil  fields,  485 
Western  Galicia  oil  fields,  524 
Wet  gas,  34,  77,  483 
Wheeler,  Oklahoma,  oil  field,  321 
White  oil,  68 


White  Oil  Springs,  Persia,  549 
White  River,  Colorado,  oil  field,  434 
Whittier,  California,  oil  field,  466 
Wichita  County,  Texas,  oil  fields,  324 
Wichita  Mountains,  Oklahoma,  276 
Williamson  County,  Texas,  oil  field, 

343 
Willis*  experiments   in   deformation, 

166 

Will-o'-the-wisp,  33 
Witherspoon-McKee  pool,  Texas,  341 
Woman's  Pocket  oil  field,  Montana, 

410 
Woodbine  sand,  350 

salt  water  in,  49 

Woodfield  quadrangle,  Ohio,  228 
Wooster  County,  Ohio,  228 
World's  oil  fields,  map  of,  8,  9 

estimated  probable  production, 

11 

Wurtzilite,  17 
Wyoming  oil  fields,  376,  377,  378 

reservoir  rocks,  55 


Yakataga,    Alaska,    oil    occurrences 

near,  472 
Yenang,  6 
Yenangyat  oil  field,  Burma,  555 

mud  dikes  of,  38 

oil  seeps  of,  22 

Yenangyaung  oil  field,  Burma,  132, 
133,  554 

mud  dikes-  of,  22,  38 

oil  springs,  22 

salt  water  of,  50 


Zabrat,  Russia,  oil  field,  540 
Zalakiec,  Galicia,  oil  field,  525 
Zeit  oil  field,  Egypt,  552 
Zorritas,  Peru,  oil  field,  587 


4  DAY  USE 

RETURN  TO  DESK  FROM  WHICH  BORROWED 

LOAN  DEPT. 

This  book  is  due  on  the  last  date  stamped  below,  or 

on  the  date  to  which  renewed. 
Renewed  books  are  subject  to  immediate  recall. 


REC'D  L.D 


FEB  12  195 


8Scp'59RX 


n 


ScP 


LD  21-100m,-6,'56 
(B9311slO)476 


General  Library 

University  of  California 

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